fix(jassub): [PKG-JASSUB-08] transfer offscreen canvas before queued rendering

docs/compiled/artplayer-plugin-jassub.js

@@ -4,4 +4,4 @@
  * (c) 2017-2026 Harvey Zhao
  * Released under the MIT License.
  */
-!function(e,t){"object"===typeof exports&&"undefined"!==typeof module?module.exports=t():"function"==typeof define&&define.amd?(e.artplayerPluginJassub=t(),define(function(){return e.artplayerPluginJassub})):(e="undefined"!==typeof globalThis?globalThis:e||self).artplayerPluginJassub=t()}(this,function(){"use strict";var e=Object.defineProperty,t=(t,s,i)=>((t,s,i)=>s in t?e(t,s,{enumerable:!0,configurable:!0,writable:!0,value:i}):t[s]=i)(t,"symbol"!==typeof s?s+"":s,i);typeof HTMLVideoElement<"u"&&!("requestVideoFrameCallback"in HTMLVideoElement.prototype)&&"getVideoPlaybackQuality"in HTMLVideoElement.prototype&&(HTMLVideoElement.prototype.requestVideoFrameCallback=function(e){Object.prototype.hasOwnProperty.call(this,"_rvfcpolyfillmap")||(this._rvfcpolyfillmap={});const t=this._rvfcpolyfillid=(this._rvfcpolyfillid||0)+1,s=performance.now(),i=this.getVideoPlaybackQuality(),a=this.currentTime,r=this.mozPresentedFrames||this.mozPaintedFrames||i.totalVideoFrames-i.droppedVideoFrames,n=(o,h)=>{if(!(t in this._rvfcpolyfillmap))return;const d=this.getVideoPlaybackQuality(),l=this.mozPresentedFrames||this.mozPaintedFrames||d.totalVideoFrames-d.droppedVideoFrames,c=l>r,_=0===r&&0===l&&0===i.totalVideoFrames&&0===i.droppedVideoFrames&&0===d.totalVideoFrames&&0===d.droppedVideoFrames&&Number.isFinite(this.currentTime)&&this.currentTime!==a&&this.readyState>=2&&!this.seeking&&h-s>=1e3/30;if(c||_){const s=this.mozFrameDelay||d.totalFrameDelay-i.totalFrameDelay||0,a=h-o;delete this._rvfcpolyfillmap[t],e(h,{presentationTime:h+1e3*s,expectedDisplayTime:h+a,width:this.videoWidth,height:this.videoHeight,mediaTime:_&&!c?Math.max(0,this.currentTime):Math.max(0,this.currentTime||0)+a/1e3,presentedFrames:l,processingDuration:s})}else this._rvfcpolyfillmap[t]=requestAnimationFrame(e=>n(h,e))};return this._rvfcpolyfillmap[t]=requestAnimationFrame(e=>n(s,e)),t},HTMLVideoElement.prototype.cancelVideoFrameCallback=function(e){const t=this._rvfcpolyfillmap;t&&e in t&&(cancelAnimationFrame(t[e]),delete t[e])});const s={bt709:"BT709",bt470bg:"BT601",smpte170m:"BT601"},i={BT601:{BT709:"1.0863 -0.0723 -0.014 0 0 0.0965 0.8451 0.0584 0 0 -0.0141 -0.0277 1.0418"},BT709:{BT601:"0.9137 0.0784 0.0079 0 0 -0.1049 1.1722 -0.0671 0 0 0.0096 0.0322 0.9582"},FCC:{BT709:"1.0873 -0.0736 -0.0137 0 0 0.0974 0.8494 0.0531 0 0 -0.0127 -0.0251 1.0378",BT601:"1.001 -0.0008 -0.0002 0 0 0.0009 1.005 -0.006 0 0 0.0013 0.0027 0.996"},SMPTE240M:{BT709:"0.9993 0.0006 0.0001 0 0 -0.0004 0.9812 0.0192 0 0 -0.0034 -0.0114 1.0148",BT601:"0.913 0.0774 0.0096 0 0 -0.1051 1.1508 -0.0456 0 0 0.0063 0.0207 0.973"}},a=class e extends EventTarget{constructor(t){let s;super(),this._requests=new Set;try{if(!globalThis.Worker)throw this.destroy("Worker not supported");if(!t)throw this.destroy("No options provided");if(this._loaded=new Promise(e=>{this._init=e}),s=e._test(),this._onDemandRender="requestVideoFrameCallback"in HTMLVideoElement.prototype&&(t.onDemandRender??!0),this._offscreenRender="transferControlToOffscreen"in HTMLCanvasElement.prototype&&!t.canvas&&(t.offscreenRender??!0),this.timeOffset=t.timeOffset||0,this._video=t.video,this._videoHeight=0,this._videoWidth=0,this._videoColorSpace=null,this._canvas=t.canvas,this._video&&!this._canvas)this._canvasParent=document.createElement("div"),this._canvasParent.className="JASSUB",this._canvasParent.style.position="relative",this._canvas=this._createCanvas(),this._video.insertAdjacentElement("afterend",this._canvasParent);else if(!this._canvas)throw this.destroy("Don't know where to render: you should give video or canvas in options.");if(this._bufferCanvas=document.createElement("canvas"),this._bufferCtx=this._bufferCanvas.getContext("2d"),!this._bufferCtx)throw this.destroy("Canvas rendering not supported");this._canvasctrl=this._offscreenRender?this._canvas.transferControlToOffscreen():this._canvas,this._ctx=!this._offscreenRender&&this._canvasctrl.getContext("2d"),this._lastRenderTime=0,this.debug=!!t.debug,this.prescaleFactor=t.prescaleFactor||1,this.prescaleHeightLimit=t.prescaleHeightLimit||1080,this.maxRenderHeight=t.maxRenderHeight||0,this._boundResize=this.resize.bind(this),this._boundTimeUpdate=this._timeupdate.bind(this),this._boundSetRate=()=>{this._destroyed||this.setRate(this._video.playbackRate)},this._boundUpdateColorSpace=this._updateColorSpace.bind(this),this._video&&this.setVideo(t.video),this._onDemandRender&&(this.busy=!1,this._lastDemandTime=null),this._worker=new Worker(t.workerUrl||"jassub-worker.js"),this._worker.onmessage=e=>this._onmessage(e),this._worker.onerror=e=>this._error(e),s.then(()=>{this._destroyed||(this._worker.postMessage({target:"init",wasmUrl:e._supportsSIMD&&t.modernWasmUrl?t.modernWasmUrl:t.wasmUrl??"jassub-worker.wasm",legacyWasmUrl:t.legacyWasmUrl??"jassub-worker.wasm.js",asyncRender:typeof createImageBitmap<"u"&&(t.asyncRender??!0),onDemandRender:this._onDemandRender,width:this._canvasctrl.width||0,height:this._canvasctrl.height||0,blendMode:t.blendMode||"js",subUrl:t.suLine truncated
+!function(e,t){"object"===typeof exports&&"undefined"!==typeof module?module.exports=t():"function"==typeof define&&define.amd?(e.artplayerPluginJassub=t(),define(function(){return e.artplayerPluginJassub})):(e="undefined"!==typeof globalThis?globalThis:e||self).artplayerPluginJassub=t()}(this,function(){"use strict";var e=Object.defineProperty,t=(t,s,i)=>((t,s,i)=>s in t?e(t,s,{enumerable:!0,configurable:!0,writable:!0,value:i}):t[s]=i)(t,"symbol"!==typeof s?s+"":s,i);typeof HTMLVideoElement<"u"&&!("requestVideoFrameCallback"in HTMLVideoElement.prototype)&&"getVideoPlaybackQuality"in HTMLVideoElement.prototype&&(HTMLVideoElement.prototype.requestVideoFrameCallback=function(e){Object.prototype.hasOwnProperty.call(this,"_rvfcpolyfillmap")||(this._rvfcpolyfillmap={});const t=this._rvfcpolyfillid=(this._rvfcpolyfillid||0)+1,s=performance.now(),i=this.getVideoPlaybackQuality(),a=this.currentTime,r=this.mozPresentedFrames||this.mozPaintedFrames||i.totalVideoFrames-i.droppedVideoFrames,n=(o,h)=>{if(!(t in this._rvfcpolyfillmap))return;const d=this.getVideoPlaybackQuality(),l=this.mozPresentedFrames||this.mozPaintedFrames||d.totalVideoFrames-d.droppedVideoFrames,c=l>r,_=0===r&&0===l&&0===i.totalVideoFrames&&0===i.droppedVideoFrames&&0===d.totalVideoFrames&&0===d.droppedVideoFrames&&Number.isFinite(this.currentTime)&&this.currentTime!==a&&this.readyState>=2&&!this.seeking&&h-s>=1e3/30;if(c||_){const s=this.mozFrameDelay||d.totalFrameDelay-i.totalFrameDelay||0,a=h-o;delete this._rvfcpolyfillmap[t],e(h,{presentationTime:h+1e3*s,expectedDisplayTime:h+a,width:this.videoWidth,height:this.videoHeight,mediaTime:_&&!c?Math.max(0,this.currentTime):Math.max(0,this.currentTime||0)+a/1e3,presentedFrames:l,processingDuration:s})}else this._rvfcpolyfillmap[t]=requestAnimationFrame(e=>n(h,e))};return this._rvfcpolyfillmap[t]=requestAnimationFrame(e=>n(s,e)),t},HTMLVideoElement.prototype.cancelVideoFrameCallback=function(e){const t=this._rvfcpolyfillmap;t&&e in t&&(cancelAnimationFrame(t[e]),delete t[e])});const s={bt709:"BT709",bt470bg:"BT601",smpte170m:"BT601"},i={BT601:{BT709:"1.0863 -0.0723 -0.014 0 0 0.0965 0.8451 0.0584 0 0 -0.0141 -0.0277 1.0418"},BT709:{BT601:"0.9137 0.0784 0.0079 0 0 -0.1049 1.1722 -0.0671 0 0 0.0096 0.0322 0.9582"},FCC:{BT709:"1.0873 -0.0736 -0.0137 0 0 0.0974 0.8494 0.0531 0 0 -0.0127 -0.0251 1.0378",BT601:"1.001 -0.0008 -0.0002 0 0 0.0009 1.005 -0.006 0 0 0.0013 0.0027 0.996"},SMPTE240M:{BT709:"0.9993 0.0006 0.0001 0 0 -0.0004 0.9812 0.0192 0 0 -0.0034 -0.0114 1.0148",BT601:"0.913 0.0774 0.0096 0 0 -0.1051 1.1508 -0.0456 0 0 0.0063 0.0207 0.973"}},a=class e extends EventTarget{constructor(t){let s;super(),this._requests=new Set;try{if(!globalThis.Worker)throw this.destroy("Worker not supported");if(!t)throw this.destroy("No options provided");if(this._loaded=new Promise(e=>{this._init=e}),s=e._test(),this._onDemandRender="requestVideoFrameCallback"in HTMLVideoElement.prototype&&(t.onDemandRender??!0),this._offscreenRender="transferControlToOffscreen"in HTMLCanvasElement.prototype&&!t.canvas&&(t.offscreenRender??!0),this.timeOffset=t.timeOffset||0,this._video=t.video,this._videoHeight=0,this._videoWidth=0,this._videoColorSpace=null,this._canvas=t.canvas,this._video&&!this._canvas)this._canvasParent=document.createElement("div"),this._canvasParent.className="JASSUB",this._canvasParent.style.position="relative",this._canvas=this._createCanvas(),this._video.insertAdjacentElement("afterend",this._canvasParent);else if(!this._canvas)throw this.destroy("Don't know where to render: you should give video or canvas in options.");if(this._bufferCanvas=document.createElement("canvas"),this._bufferCtx=this._bufferCanvas.getContext("2d"),!this._bufferCtx)throw this.destroy("Canvas rendering not supported");this._canvasctrl=this._offscreenRender?this._canvas.transferControlToOffscreen():this._canvas,this._ctx=!this._offscreenRender&&this._canvasctrl.getContext("2d"),this._lastRenderTime=0,this.debug=!!t.debug,this.prescaleFactor=t.prescaleFactor||1,this.prescaleHeightLimit=t.prescaleHeightLimit||1080,this.maxRenderHeight=t.maxRenderHeight||0,this._boundResize=this.resize.bind(this),this._boundTimeUpdate=this._timeupdate.bind(this),this._boundSetRate=()=>{this._destroyed||this.setRate(this._video.playbackRate)},this._boundUpdateColorSpace=this._updateColorSpace.bind(this),this._video&&this.setVideo(t.video),this._onDemandRender&&(this.busy=!1,this._lastDemandTime=null),this._worker=new Worker(t.workerUrl||"jassub-worker.js"),this._worker.onmessage=e=>this._onmessage(e),this._worker.onerror=e=>this._error(e),s.then(()=>{this._destroyed||this._worker.postMessage({target:"init",wasmUrl:e._supportsSIMD&&t.modernWasmUrl?t.modernWasmUrl:t.wasmUrl??"jassub-worker.wasm",legacyWasmUrl:t.legacyWasmUrl??"jassub-worker.wasm.js",asyncRender:typeof createImageBitmap<"u"&&(t.asyncRender??!0),onDemandRender:this._onDemandRender,width:this._canvasctrl.width||0,height:this._canvasctrl.height||0,blendMode:t.blendMode||"js",subUrl:t.subLine truncated

docs/compiled/artplayer-plugin-jassub.legacy.js

@@ -4,4 +4,4 @@
  * (c) 2017-2026 Harvey Zhao
  * Released under the MIT License.
  */
-!function(e,t){"object"===typeof exports&&"undefined"!==typeof module?module.exports=t():"function"==typeof define&&define.amd?(e.artplayerPluginJassub=t(),define(function(){return e.artplayerPluginJassub})):(e="undefined"!==typeof globalThis?globalThis:e||self).artplayerPluginJassub=t()}(this,function(){"use strict";var e=Object.defineProperty,t=Object.getOwnPropertySymbols,s=Object.prototype.hasOwnProperty,i=Object.prototype.propertyIsEnumerable,a=(t,s,i)=>s in t?e(t,s,{enumerable:!0,configurable:!0,writable:!0,value:i}):t[s]=i,r=(e,r)=>{for(var n in r||(r={}))s.call(r,n)&&a(e,n,r[n]);if(t)for(var n of t(r))i.call(r,n)&&a(e,n,r[n]);return e},n=(e,t,s)=>a(e,"symbol"!==typeof t?t+"":t,s),o=(e,t,s)=>new Promise((i,a)=>{var r=e=>{try{o(s.next(e))}catch(t){a(t)}},n=e=>{try{o(s.throw(e))}catch(t){a(t)}},o=e=>e.done?i(e.value):Promise.resolve(e.value).then(r,n);o((s=s.apply(e,t)).next())});typeof HTMLVideoElement<"u"&&!("requestVideoFrameCallback"in HTMLVideoElement.prototype)&&"getVideoPlaybackQuality"in HTMLVideoElement.prototype&&(HTMLVideoElement.prototype.requestVideoFrameCallback=function(e){Object.prototype.hasOwnProperty.call(this,"_rvfcpolyfillmap")||(this._rvfcpolyfillmap={});const t=this._rvfcpolyfillid=(this._rvfcpolyfillid||0)+1,s=performance.now(),i=this.getVideoPlaybackQuality(),a=this.currentTime,r=this.mozPresentedFrames||this.mozPaintedFrames||i.totalVideoFrames-i.droppedVideoFrames,n=(o,h)=>{if(!(t in this._rvfcpolyfillmap))return;const d=this.getVideoPlaybackQuality(),l=this.mozPresentedFrames||this.mozPaintedFrames||d.totalVideoFrames-d.droppedVideoFrames,c=l>r,_=0===r&&0===l&&0===i.totalVideoFrames&&0===i.droppedVideoFrames&&0===d.totalVideoFrames&&0===d.droppedVideoFrames&&Number.isFinite(this.currentTime)&&this.currentTime!==a&&this.readyState>=2&&!this.seeking&&h-s>=1e3/30;if(c||_){const s=this.mozFrameDelay||d.totalFrameDelay-i.totalFrameDelay||0,a=h-o;delete this._rvfcpolyfillmap[t],e(h,{presentationTime:h+1e3*s,expectedDisplayTime:h+a,width:this.videoWidth,height:this.videoHeight,mediaTime:_&&!c?Math.max(0,this.currentTime):Math.max(0,this.currentTime||0)+a/1e3,presentedFrames:l,processingDuration:s})}else this._rvfcpolyfillmap[t]=requestAnimationFrame(e=>n(h,e))};return this._rvfcpolyfillmap[t]=requestAnimationFrame(e=>n(s,e)),t},HTMLVideoElement.prototype.cancelVideoFrameCallback=function(e){const t=this._rvfcpolyfillmap;t&&e in t&&(cancelAnimationFrame(t[e]),delete t[e])});const h={bt709:"BT709",bt470bg:"BT601",smpte170m:"BT601"},d={BT601:{BT709:"1.0863 -0.0723 -0.014 0 0 0.0965 0.8451 0.0584 0 0 -0.0141 -0.0277 1.0418"},BT709:{BT601:"0.9137 0.0784 0.0079 0 0 -0.1049 1.1722 -0.0671 0 0 0.0096 0.0322 0.9582"},FCC:{BT709:"1.0873 -0.0736 -0.0137 0 0 0.0974 0.8494 0.0531 0 0 -0.0127 -0.0251 1.0378",BT601:"1.001 -0.0008 -0.0002 0 0 0.0009 1.005 -0.006 0 0 0.0013 0.0027 0.996"},SMPTE240M:{BT709:"0.9993 0.0006 0.0001 0 0 -0.0004 0.9812 0.0192 0 0 -0.0034 -0.0114 1.0148",BT601:"0.913 0.0774 0.0096 0 0 -0.1051 1.1508 -0.0456 0 0 0.0063 0.0207 0.973"}},l=class e extends EventTarget{constructor(t){var s,i;let a;super(),this._requests=new Set;try{if(!globalThis.Worker)throw this.destroy("Worker not supported");if(!t)throw this.destroy("No options provided");if(this._loaded=new Promise(e=>{this._init=e}),a=e._test(),this._onDemandRender="requestVideoFrameCallback"in HTMLVideoElement.prototype&&(null==(s=t.onDemandRender)||s),this._offscreenRender="transferControlToOffscreen"in HTMLCanvasElement.prototype&&!t.canvas&&(null==(i=t.offscreenRender)||i),this.timeOffset=t.timeOffset||0,this._video=t.video,this._videoHeight=0,this._videoWidth=0,this._videoColorSpace=null,this._canvas=t.canvas,this._video&&!this._canvas)this._canvasParent=document.createElement("div"),this._canvasParent.className="JASSUB",this._canvasParent.style.position="relative",this._canvas=this._createCanvas(),this._video.insertAdjacentElement("afterend",this._canvasParent);else if(!this._canvas)throw this.destroy("Don't know where to render: you should give video or canvas in options.");if(this._bufferCanvas=document.createElement("canvas"),this._bufferCtx=this._bufferCanvas.getContext("2d"),!this._bufferCtx)throw this.destroy("Canvas rendering not supported");this._canvasctrl=this._offscreenRender?this._canvas.transferControlToOffscreen():this._canvas,this._ctx=!this._offscreenRender&&this._canvasctrl.getContext("2d"),this._lastRenderTime=0,this.debug=!!t.debug,this.prescaleFactor=t.prescaleFactor||1,this.prescaleHeightLimit=t.prescaleHeightLimit||1080,this.maxRenderHeight=t.maxRenderHeight||0,this._boundResize=this.resize.bind(this),this._boundTimeUpdate=this._timeupdate.bind(this),this._boundSetRate=()=>{this._destroyed||this.setRate(this._video.playbackRate)},this._boundUpdateColorSpace=this._updateColorSpace.bind(this),this._video&&this.setVideo(t.video),this._onDemandRender&&(this.busy=!1,this._lastDemandTime=null),this._worker=new Worker(t.workerUrl||"jassub-worker.js"),this._worker.onmessage=e=>this._onmessage(e),this._Line truncated
+!function(e,t){"object"===typeof exports&&"undefined"!==typeof module?module.exports=t():"function"==typeof define&&define.amd?(e.artplayerPluginJassub=t(),define(function(){return e.artplayerPluginJassub})):(e="undefined"!==typeof globalThis?globalThis:e||self).artplayerPluginJassub=t()}(this,function(){"use strict";var e=Object.defineProperty,t=Object.getOwnPropertySymbols,s=Object.prototype.hasOwnProperty,i=Object.prototype.propertyIsEnumerable,a=(t,s,i)=>s in t?e(t,s,{enumerable:!0,configurable:!0,writable:!0,value:i}):t[s]=i,r=(e,r)=>{for(var n in r||(r={}))s.call(r,n)&&a(e,n,r[n]);if(t)for(var n of t(r))i.call(r,n)&&a(e,n,r[n]);return e},n=(e,t,s)=>a(e,"symbol"!==typeof t?t+"":t,s),o=(e,t,s)=>new Promise((i,a)=>{var r=e=>{try{o(s.next(e))}catch(t){a(t)}},n=e=>{try{o(s.throw(e))}catch(t){a(t)}},o=e=>e.done?i(e.value):Promise.resolve(e.value).then(r,n);o((s=s.apply(e,t)).next())});typeof HTMLVideoElement<"u"&&!("requestVideoFrameCallback"in HTMLVideoElement.prototype)&&"getVideoPlaybackQuality"in HTMLVideoElement.prototype&&(HTMLVideoElement.prototype.requestVideoFrameCallback=function(e){Object.prototype.hasOwnProperty.call(this,"_rvfcpolyfillmap")||(this._rvfcpolyfillmap={});const t=this._rvfcpolyfillid=(this._rvfcpolyfillid||0)+1,s=performance.now(),i=this.getVideoPlaybackQuality(),a=this.currentTime,r=this.mozPresentedFrames||this.mozPaintedFrames||i.totalVideoFrames-i.droppedVideoFrames,n=(o,h)=>{if(!(t in this._rvfcpolyfillmap))return;const d=this.getVideoPlaybackQuality(),l=this.mozPresentedFrames||this.mozPaintedFrames||d.totalVideoFrames-d.droppedVideoFrames,c=l>r,_=0===r&&0===l&&0===i.totalVideoFrames&&0===i.droppedVideoFrames&&0===d.totalVideoFrames&&0===d.droppedVideoFrames&&Number.isFinite(this.currentTime)&&this.currentTime!==a&&this.readyState>=2&&!this.seeking&&h-s>=1e3/30;if(c||_){const s=this.mozFrameDelay||d.totalFrameDelay-i.totalFrameDelay||0,a=h-o;delete this._rvfcpolyfillmap[t],e(h,{presentationTime:h+1e3*s,expectedDisplayTime:h+a,width:this.videoWidth,height:this.videoHeight,mediaTime:_&&!c?Math.max(0,this.currentTime):Math.max(0,this.currentTime||0)+a/1e3,presentedFrames:l,processingDuration:s})}else this._rvfcpolyfillmap[t]=requestAnimationFrame(e=>n(h,e))};return this._rvfcpolyfillmap[t]=requestAnimationFrame(e=>n(s,e)),t},HTMLVideoElement.prototype.cancelVideoFrameCallback=function(e){const t=this._rvfcpolyfillmap;t&&e in t&&(cancelAnimationFrame(t[e]),delete t[e])});const h={bt709:"BT709",bt470bg:"BT601",smpte170m:"BT601"},d={BT601:{BT709:"1.0863 -0.0723 -0.014 0 0 0.0965 0.8451 0.0584 0 0 -0.0141 -0.0277 1.0418"},BT709:{BT601:"0.9137 0.0784 0.0079 0 0 -0.1049 1.1722 -0.0671 0 0 0.0096 0.0322 0.9582"},FCC:{BT709:"1.0873 -0.0736 -0.0137 0 0 0.0974 0.8494 0.0531 0 0 -0.0127 -0.0251 1.0378",BT601:"1.001 -0.0008 -0.0002 0 0 0.0009 1.005 -0.006 0 0 0.0013 0.0027 0.996"},SMPTE240M:{BT709:"0.9993 0.0006 0.0001 0 0 -0.0004 0.9812 0.0192 0 0 -0.0034 -0.0114 1.0148",BT601:"0.913 0.0774 0.0096 0 0 -0.1051 1.1508 -0.0456 0 0 0.0063 0.0207 0.973"}},l=class e extends EventTarget{constructor(t){var s,i;let a;super(),this._requests=new Set;try{if(!globalThis.Worker)throw this.destroy("Worker not supported");if(!t)throw this.destroy("No options provided");if(this._loaded=new Promise(e=>{this._init=e}),a=e._test(),this._onDemandRender="requestVideoFrameCallback"in HTMLVideoElement.prototype&&(null==(s=t.onDemandRender)||s),this._offscreenRender="transferControlToOffscreen"in HTMLCanvasElement.prototype&&!t.canvas&&(null==(i=t.offscreenRender)||i),this.timeOffset=t.timeOffset||0,this._video=t.video,this._videoHeight=0,this._videoWidth=0,this._videoColorSpace=null,this._canvas=t.canvas,this._video&&!this._canvas)this._canvasParent=document.createElement("div"),this._canvasParent.className="JASSUB",this._canvasParent.style.position="relative",this._canvas=this._createCanvas(),this._video.insertAdjacentElement("afterend",this._canvasParent);else if(!this._canvas)throw this.destroy("Don't know where to render: you should give video or canvas in options.");if(this._bufferCanvas=document.createElement("canvas"),this._bufferCtx=this._bufferCanvas.getContext("2d"),!this._bufferCtx)throw this.destroy("Canvas rendering not supported");this._canvasctrl=this._offscreenRender?this._canvas.transferControlToOffscreen():this._canvas,this._ctx=!this._offscreenRender&&this._canvasctrl.getContext("2d"),this._lastRenderTime=0,this.debug=!!t.debug,this.prescaleFactor=t.prescaleFactor||1,this.prescaleHeightLimit=t.prescaleHeightLimit||1080,this.maxRenderHeight=t.maxRenderHeight||0,this._boundResize=this.resize.bind(this),this._boundTimeUpdate=this._timeupdate.bind(this),this._boundSetRate=()=>{this._destroyed||this.setRate(this._video.playbackRate)},this._boundUpdateColorSpace=this._updateColorSpace.bind(this),this._video&&this.setVideo(t.video),this._onDemandRender&&(this.busy=!1,this._lastDemandTime=null),this._worker=new Worker(t.workerUrl||"jassub-worker.js"),this._worker.onmessage=e=>this._onmessage(e),this._Line truncated

docs/compiled/artplayer-plugin-jassub.mjs

@@ -147,7 +147,7 @@ const _o = class _o extends EventTarget {
           // @ts-ignore
           useLocalFonts: typeof queryLocalFonts < "u" && (e.useLocalFonts ?? true),
           hasBitmapBug: _o._hasBitmapBug
-        }), this._offscreenRender === true && this.sendMessage("offscreenCanvas", null, [this._canvasctrl]);
+        });
       }).catch((error) => {
         if (!this._destroyed) this.destroy(error);
       });
@@ -581,6 +581,10 @@ const _o = class _o extends EventTarget {
   }
   _ready() {
     if (this._destroyed) return;
+    if (this._offscreenRender === true && !this._initialOffscreenSent) {
+      this._initialOffscreenSent = true;
+      this._worker.postMessage({ target: "offscreenCanvas", transferable: [this._canvasctrl] }, [this._canvasctrl]);
+    }
     this._init(), this.dispatchEvent(new CustomEvent("ready"));
   }
   /**

package.json

@@ -51,7 +51,7 @@
     "ci:build": "yarn build:types && yarn build all && yarn build:i18n && yarn build:ts && yarn build:docs && yarn test:imports",
     "test:imports": "node --test test/esm.test.js test/i18n.test.js test/ssr.test.js test/asr-distribution.test.js",
     "typecheck": "node scripts/typecheck.mjs",
-    "test:unit": "node --test test/danmuku-setting.test.js test/danmuku-heatmap.test.js test/danmuku-renderer.test.js test/danmuku-scheduler.test.js test/danmuku-worker-client.test.js test/danmuku-input.test.js test/danmuku-parser.test.js test/danmuku-failures.test.js test/danmuku-mask-failures.test.js test/danmuku-mask-lifecycle.test.js test/asr-encoding.test.js test/asr-lifecycle.test.js test/asr-audio.test.js test/asr.test.js test/jassub.test.js test/jassub-registration.test.js test/jassub-runtime.test.js test/jassub-vendor-lifecycle.test.js test/jassub-frame-polyfill.test.js test/multiple-subtitles-merge.test.js test/multiple-subtitles-lifecycle.test.js test/multiple-subtitles-failures.test.js test/multiple-subtitles.test.js test/multiple-subtitles-vendor.test.js test/vtt-thumbnail-parser.test.js test/vtt-thumbnail-lifecycle.test.js test/vtt-thumbnail.test.js test/auto-thumbnail-frames.test.js test/auto-thumbnail-lifecycle.test.js test/auto-thumbnail.test.js test/thumbnail-emitter.test.js test/thumbnail-runtime.test.js test/thumbnail-vendor.test.js test/thumbnail-lifecycle.test.js test/thumbnail-input.test.js test/thumbnail.test.js test/iframe-navigation.test.js test/iframe-boundaries.test.js test/iframe-lifecycle.test.js test/iframe.test.js test/mediabunny.test.js test/mediabunny-shim.test.js test/mediabunny-coordination.test.js test/mediabunny-video.test.js test/mediabunny-audio.test.js test/mediabunny-hls.test.js test/mediabunny-entry.test.js test/mediabunny-capability.test.js test/mediabunny-load.test.js test/mediabunny-input.test.js test/dpip.test.js test/dpip-lifecycle.test.js test/canvas.test.js test/canvas-lifecycle.test.js test/ambilight.test.js test/ambilight-lifecycle.test.js test/ambilight-proxy.test.js test/vast.test.js test/vast-lifecycle.test.js test/ads.test.js test/ads-lifecycle.test.js test/playback.test.js test/dash-control.test.js test/dash-contract.test.js test/dash-lifecycle.test.js test/dash-events.test.js test/hls-control.test.js test/audio-track.test.js test/public-behavior.test.js test/helpers.test.js test/chapter.test.js test/utils.test.js test/resource-scope.test.js test/instance-lifecycle.test.js test/options.test.js test/media-hosts.test.js test/plugins.test.js test/source.test.js test/playback-properties.test.js test/media-events.test.js test/template-resources.test.js test/core-vendor.test.js test/component-resources.test.js test/setting-model.test.js test/setting-layout.test.js test/setting-resources.test.js test/subtitle.test.js test/display-native.test.js test/display-video-fullscreen.test.js test/display-pip.test.js test/display-mini.test.js test/display-sizing.test.js test/display-orientation.test.js test/hotkey.test.js test/listener-registry.test.js test/global-events.test.js test/pointer-events.test.js test/gesture.test.js test/event-scheduling.test.js test/notice.test.js test/fast-forward.test.js test/auto-playback.test.js test/builtin-layers.test.js test/prompt-components.test.js test/screenshot.test.js test/thumbnails.test.js test/progress.test.js test/environment.test.js test/storage.test.js test/facade-properties.test.js test/dom-boundaries.test.js test/initialization.test.js test/entry.test.js test/accessibility-button.test.js test/accessibility-focus.test.js test/accessibility-slider.test.js test/asr-fallback-routing.test.js test/asr-local-example.test.js test/asr-explicit-capture.test.js test/chromecast.test.js test/chromecast-failures.test.js test/chromecast-runtime.test.js",
+    "test:unit": "node --test test/danmuku-setting.test.js test/danmuku-heatmap.test.js test/danmuku-renderer.test.js test/danmuku-scheduler.test.js test/danmuku-worker-client.test.js test/danmuku-input.test.js test/danmuku-parser.test.js test/danmuku-failures.test.js test/danmuku-mask-failures.test.js test/danmuku-mask-lifecycle.test.js test/asr-encoding.test.js test/asr-lifecycle.test.js test/asr-audio.test.js test/asr.test.js test/jassub.test.js test/jassub-registration.test.js test/jassub-runtime.test.js test/jassub-vendor-lifecycle.test.js test/jassub-frame-polyfill.test.js test/jassub-offscreen.test.js test/multiple-subtitles-merge.test.js test/multiple-subtitles-lifecycle.test.js test/multiple-subtitles-failures.test.js test/multiple-subtitles.test.js test/multiple-subtitles-vendor.test.js test/vtt-thumbnail-parser.test.js test/vtt-thumbnail-lifecycle.test.js test/vtt-thumbnail.test.js test/auto-thumbnail-frames.test.js test/auto-thumbnail-lifecycle.test.js test/auto-thumbnail.test.js test/thumbnail-emitter.test.js test/thumbnail-runtime.test.js test/thumbnail-vendor.test.js test/thumbnail-lifecycle.test.js test/thumbnail-input.test.js test/thumbnail.test.js test/iframe-navigation.test.js test/iframe-boundaries.test.js test/iframe-lifecycle.test.js test/iframe.test.js test/mediabunny.test.js test/mediabunny-shim.test.js test/mediabunny-coordination.test.js test/mediabunny-video.test.js test/mediabunny-audio.test.js test/mediabunny-hls.test.js test/mediabunny-entry.test.js test/mediabunny-capability.test.js test/mediabunny-load.test.js test/mediabunny-input.test.js test/dpip.test.js test/dpip-lifecycle.test.js test/canvas.test.js test/canvas-lifecycle.test.js test/ambilight.test.js test/ambilight-lifecycle.test.js test/ambilight-proxy.test.js test/vast.test.js test/vast-lifecycle.test.js test/ads.test.js test/ads-lifecycle.test.js test/playback.test.js test/dash-control.test.js test/dash-contract.test.js test/dash-lifecycle.test.js test/dash-events.test.js test/hls-control.test.js test/audio-track.test.js test/public-behavior.test.js test/helpers.test.js test/chapter.test.js test/utils.test.js test/resource-scope.test.js test/instance-lifecycle.test.js test/options.test.js test/media-hosts.test.js test/plugins.test.js test/source.test.js test/playback-properties.test.js test/media-events.test.js test/template-resources.test.js test/core-vendor.test.js test/component-resources.test.js test/setting-model.test.js test/setting-layout.test.js test/setting-resources.test.js test/subtitle.test.js test/display-native.test.js test/display-video-fullscreen.test.js test/display-pip.test.js test/display-mini.test.js test/display-sizing.test.js test/display-orientation.test.js test/hotkey.test.js test/listener-registry.test.js test/global-events.test.js test/pointer-events.test.js test/gesture.test.js test/event-scheduling.test.js test/notice.test.js test/fast-forward.test.js test/auto-playback.test.js test/builtin-layers.test.js test/prompt-components.test.js test/screenshot.test.js test/thumbnails.test.js test/progress.test.js test/environment.test.js test/storage.test.js test/facade-properties.test.js test/dom-boundaries.test.js test/initialization.test.js test/entry.test.js test/accessibility-button.test.js test/accessibility-focus.test.js test/accessibility-slider.test.js test/asr-fallback-routing.test.js test/asr-local-example.test.js test/asr-explicit-capture.test.js test/chromecast.test.js test/chromecast-failures.test.js test/chromecast-runtime.test.js",
     "test:coverage": "node --test test/coverage.test.js && node scripts/coverage.mjs",
     "test": "yarn test:node && yarn test:baseline",
     "test:browser": "playwright test",
@@ -90,7 +90,7 @@
     "test:vtt-thumbnail-types-package": "node refactor/scripts/vtt-thumbnail-package-types.mjs",
     "test:multiple-subtitles": "node --test test/multiple-subtitles-merge.test.js test/multiple-subtitles-lifecycle.test.js test/multiple-subtitles-failures.test.js test/multiple-subtitles.test.js test/multiple-subtitles-vendor.test.js refactor/scripts/multiple-subtitles-contract.test.mjs refactor/scripts/multiple-subtitles-runtime-types.test.mjs refactor/scripts/multiple-subtitles-types.test.mjs",
     "test:multiple-subtitles-types-package": "node refactor/scripts/multiple-subtitles-package-types.mjs",
-    "test:jassub": "node --test test/jassub.test.js test/jassub-registration.test.js test/jassub-runtime.test.js test/jassub-vendor-lifecycle.test.js test/jassub-frame-polyfill.test.js refactor/scripts/jassub-contract.test.mjs refactor/scripts/jassub-provenance.test.mjs refactor/scripts/jassub-failures.test.mjs refactor/scripts/jassub-types.test.mjs refactor/scripts/jassub-vendor-patch.test.mjs",
+    "test:jassub": "node --test test/jassub.test.js test/jassub-registration.test.js test/jassub-runtime.test.js test/jassub-vendor-lifecycle.test.js test/jassub-frame-polyfill.test.js test/jassub-offscreen.test.js refactor/scripts/jassub-contract.test.mjs refactor/scripts/jassub-provenance.test.mjs refactor/scripts/jassub-failures.test.mjs refactor/scripts/jassub-types.test.mjs refactor/scripts/jassub-vendor-patch.test.mjs",
     "test:jassub-types": "node --test refactor/scripts/jassub-types.test.mjs",
     "test:jassub-types-package": "node refactor/scripts/jassub-package-types.mjs",
     "check:ci": "node refactor/scripts/ci-workflow.mjs",

packages/artplayer-plugin-jassub/ARCHITECTURE.md

@@ -72,7 +72,15 @@ The original wrapper matched upstream jassub 1.8.8 apart from formatting and the
 PKG-JASSUB-07 records its local lifecycle/clock patch separately in
 `../../refactor/baselines/jassub-vendor-patch.json` and the accompanying patch file.
 Keep original and patched fingerprints distinct; do not call the changed wrapper an
-unmodified upstream file. The
+unmodified upstream file. PKG-JASSUB-08 adds a separate follow-up patch in
+`../../refactor/baselines/jassub-offscreen-patch.json`: initial offscreen ownership
+is transferred synchronously when the Worker reports ready, before resolving the
+loaded gate and dispatching the public ready event. Otherwise a queued resize can
+ask the Worker to return main-thread images while the instance has no main-thread
+context. Duplicate ready delivery must not transfer the same canvas twice. The
+explicit main-thread/custom-canvas and unsupported-capability paths keep their
+existing selection. Later hybrid detach/reattach remains separate and must retain
+its own rendering/lifetime checks. The
 worker JS and default font match that archive byte-for-byte. Local WASM instead matches
 the exact Pages nightly blobs associated with source 6b19a04ddfbad8f9bfd3237395788dd76218841b.
 Its build workflow and seven submodule revisions are pinned in the separate
@@ -123,6 +131,11 @@ The candidate's default onDemandRender path is tested through playback/seek/layo
 Chromium/Firefox/WebKit. jassub-lifecycle.spec.js additionally checks actual replacement
 video pixels, numerical fallback playbackRate, repeated teardown, invalid-URL constructor
 rollback and a genuine asynchronous CSP Worker error reaching a pending query. These
-are distinct from default offscreen mode, full devices and sustained memory/GPU release,
+are distinct from full devices and sustained memory/GPU release, which remain
-which remain unverified. See
+unverified. Set ARTPLAYER_JASSUB_OFFSCREEN=default to omit the option and exercise
+the browser's actual default selection. The test copies the displayed canvas bitmap
+to a separate readback canvas, so it supports both transferred and main-thread
+canvases. PKG-JASSUB-08 records default-mode Chromium/Firefox rendering and WebKit's
+capability fallback separately; this does not prove physical Safari/mobile behavior.
+See
 `../../refactor/baselines/jassub-contract.md` for precise contract and provenance evidence.

packages/artplayer-plugin-jassub/dist/artplayer-plugin-jassub.js

@@ -4,4 +4,4 @@
  * (c) 2017-2026 Harvey Zhao
  * Released under the MIT License.
  */
-!function(e,t){"object"===typeof exports&&"undefined"!==typeof module?module.exports=t():"function"==typeof define&&define.amd?(e.artplayerPluginJassub=t(),define(function(){return e.artplayerPluginJassub})):(e="undefined"!==typeof globalThis?globalThis:e||self).artplayerPluginJassub=t()}(this,function(){"use strict";var e=Object.defineProperty,t=(t,s,i)=>((t,s,i)=>s in t?e(t,s,{enumerable:!0,configurable:!0,writable:!0,value:i}):t[s]=i)(t,"symbol"!==typeof s?s+"":s,i);typeof HTMLVideoElement<"u"&&!("requestVideoFrameCallback"in HTMLVideoElement.prototype)&&"getVideoPlaybackQuality"in HTMLVideoElement.prototype&&(HTMLVideoElement.prototype.requestVideoFrameCallback=function(e){Object.prototype.hasOwnProperty.call(this,"_rvfcpolyfillmap")||(this._rvfcpolyfillmap={});const t=this._rvfcpolyfillid=(this._rvfcpolyfillid||0)+1,s=performance.now(),i=this.getVideoPlaybackQuality(),a=this.currentTime,r=this.mozPresentedFrames||this.mozPaintedFrames||i.totalVideoFrames-i.droppedVideoFrames,n=(o,h)=>{if(!(t in this._rvfcpolyfillmap))return;const d=this.getVideoPlaybackQuality(),l=this.mozPresentedFrames||this.mozPaintedFrames||d.totalVideoFrames-d.droppedVideoFrames,c=l>r,_=0===r&&0===l&&0===i.totalVideoFrames&&0===i.droppedVideoFrames&&0===d.totalVideoFrames&&0===d.droppedVideoFrames&&Number.isFinite(this.currentTime)&&this.currentTime!==a&&this.readyState>=2&&!this.seeking&&h-s>=1e3/30;if(c||_){const s=this.mozFrameDelay||d.totalFrameDelay-i.totalFrameDelay||0,a=h-o;delete this._rvfcpolyfillmap[t],e(h,{presentationTime:h+1e3*s,expectedDisplayTime:h+a,width:this.videoWidth,height:this.videoHeight,mediaTime:_&&!c?Math.max(0,this.currentTime):Math.max(0,this.currentTime||0)+a/1e3,presentedFrames:l,processingDuration:s})}else this._rvfcpolyfillmap[t]=requestAnimationFrame(e=>n(h,e))};return this._rvfcpolyfillmap[t]=requestAnimationFrame(e=>n(s,e)),t},HTMLVideoElement.prototype.cancelVideoFrameCallback=function(e){const t=this._rvfcpolyfillmap;t&&e in t&&(cancelAnimationFrame(t[e]),delete t[e])});const s={bt709:"BT709",bt470bg:"BT601",smpte170m:"BT601"},i={BT601:{BT709:"1.0863 -0.0723 -0.014 0 0 0.0965 0.8451 0.0584 0 0 -0.0141 -0.0277 1.0418"},BT709:{BT601:"0.9137 0.0784 0.0079 0 0 -0.1049 1.1722 -0.0671 0 0 0.0096 0.0322 0.9582"},FCC:{BT709:"1.0873 -0.0736 -0.0137 0 0 0.0974 0.8494 0.0531 0 0 -0.0127 -0.0251 1.0378",BT601:"1.001 -0.0008 -0.0002 0 0 0.0009 1.005 -0.006 0 0 0.0013 0.0027 0.996"},SMPTE240M:{BT709:"0.9993 0.0006 0.0001 0 0 -0.0004 0.9812 0.0192 0 0 -0.0034 -0.0114 1.0148",BT601:"0.913 0.0774 0.0096 0 0 -0.1051 1.1508 -0.0456 0 0 0.0063 0.0207 0.973"}},a=class e extends EventTarget{constructor(t){let s;super(),this._requests=new Set;try{if(!globalThis.Worker)throw this.destroy("Worker not supported");if(!t)throw this.destroy("No options provided");if(this._loaded=new Promise(e=>{this._init=e}),s=e._test(),this._onDemandRender="requestVideoFrameCallback"in HTMLVideoElement.prototype&&(t.onDemandRender??!0),this._offscreenRender="transferControlToOffscreen"in HTMLCanvasElement.prototype&&!t.canvas&&(t.offscreenRender??!0),this.timeOffset=t.timeOffset||0,this._video=t.video,this._videoHeight=0,this._videoWidth=0,this._videoColorSpace=null,this._canvas=t.canvas,this._video&&!this._canvas)this._canvasParent=document.createElement("div"),this._canvasParent.className="JASSUB",this._canvasParent.style.position="relative",this._canvas=this._createCanvas(),this._video.insertAdjacentElement("afterend",this._canvasParent);else if(!this._canvas)throw this.destroy("Don't know where to render: you should give video or canvas in options.");if(this._bufferCanvas=document.createElement("canvas"),this._bufferCtx=this._bufferCanvas.getContext("2d"),!this._bufferCtx)throw this.destroy("Canvas rendering not supported");this._canvasctrl=this._offscreenRender?this._canvas.transferControlToOffscreen():this._canvas,this._ctx=!this._offscreenRender&&this._canvasctrl.getContext("2d"),this._lastRenderTime=0,this.debug=!!t.debug,this.prescaleFactor=t.prescaleFactor||1,this.prescaleHeightLimit=t.prescaleHeightLimit||1080,this.maxRenderHeight=t.maxRenderHeight||0,this._boundResize=this.resize.bind(this),this._boundTimeUpdate=this._timeupdate.bind(this),this._boundSetRate=()=>{this._destroyed||this.setRate(this._video.playbackRate)},this._boundUpdateColorSpace=this._updateColorSpace.bind(this),this._video&&this.setVideo(t.video),this._onDemandRender&&(this.busy=!1,this._lastDemandTime=null),this._worker=new Worker(t.workerUrl||"jassub-worker.js"),this._worker.onmessage=e=>this._onmessage(e),this._worker.onerror=e=>this._error(e),s.then(()=>{this._destroyed||(this._worker.postMessage({target:"init",wasmUrl:e._supportsSIMD&&t.modernWasmUrl?t.modernWasmUrl:t.wasmUrl??"jassub-worker.wasm",legacyWasmUrl:t.legacyWasmUrl??"jassub-worker.wasm.js",asyncRender:typeof createImageBitmap<"u"&&(t.asyncRender??!0),onDemandRender:this._onDemandRender,width:this._canvasctrl.width||0,height:this._canvasctrl.height||0,blendMode:t.blendMode||"js",subUrl:t.suLine truncated
+!function(e,t){"object"===typeof exports&&"undefined"!==typeof module?module.exports=t():"function"==typeof define&&define.amd?(e.artplayerPluginJassub=t(),define(function(){return e.artplayerPluginJassub})):(e="undefined"!==typeof globalThis?globalThis:e||self).artplayerPluginJassub=t()}(this,function(){"use strict";var e=Object.defineProperty,t=(t,s,i)=>((t,s,i)=>s in t?e(t,s,{enumerable:!0,configurable:!0,writable:!0,value:i}):t[s]=i)(t,"symbol"!==typeof s?s+"":s,i);typeof HTMLVideoElement<"u"&&!("requestVideoFrameCallback"in HTMLVideoElement.prototype)&&"getVideoPlaybackQuality"in HTMLVideoElement.prototype&&(HTMLVideoElement.prototype.requestVideoFrameCallback=function(e){Object.prototype.hasOwnProperty.call(this,"_rvfcpolyfillmap")||(this._rvfcpolyfillmap={});const t=this._rvfcpolyfillid=(this._rvfcpolyfillid||0)+1,s=performance.now(),i=this.getVideoPlaybackQuality(),a=this.currentTime,r=this.mozPresentedFrames||this.mozPaintedFrames||i.totalVideoFrames-i.droppedVideoFrames,n=(o,h)=>{if(!(t in this._rvfcpolyfillmap))return;const d=this.getVideoPlaybackQuality(),l=this.mozPresentedFrames||this.mozPaintedFrames||d.totalVideoFrames-d.droppedVideoFrames,c=l>r,_=0===r&&0===l&&0===i.totalVideoFrames&&0===i.droppedVideoFrames&&0===d.totalVideoFrames&&0===d.droppedVideoFrames&&Number.isFinite(this.currentTime)&&this.currentTime!==a&&this.readyState>=2&&!this.seeking&&h-s>=1e3/30;if(c||_){const s=this.mozFrameDelay||d.totalFrameDelay-i.totalFrameDelay||0,a=h-o;delete this._rvfcpolyfillmap[t],e(h,{presentationTime:h+1e3*s,expectedDisplayTime:h+a,width:this.videoWidth,height:this.videoHeight,mediaTime:_&&!c?Math.max(0,this.currentTime):Math.max(0,this.currentTime||0)+a/1e3,presentedFrames:l,processingDuration:s})}else this._rvfcpolyfillmap[t]=requestAnimationFrame(e=>n(h,e))};return this._rvfcpolyfillmap[t]=requestAnimationFrame(e=>n(s,e)),t},HTMLVideoElement.prototype.cancelVideoFrameCallback=function(e){const t=this._rvfcpolyfillmap;t&&e in t&&(cancelAnimationFrame(t[e]),delete t[e])});const s={bt709:"BT709",bt470bg:"BT601",smpte170m:"BT601"},i={BT601:{BT709:"1.0863 -0.0723 -0.014 0 0 0.0965 0.8451 0.0584 0 0 -0.0141 -0.0277 1.0418"},BT709:{BT601:"0.9137 0.0784 0.0079 0 0 -0.1049 1.1722 -0.0671 0 0 0.0096 0.0322 0.9582"},FCC:{BT709:"1.0873 -0.0736 -0.0137 0 0 0.0974 0.8494 0.0531 0 0 -0.0127 -0.0251 1.0378",BT601:"1.001 -0.0008 -0.0002 0 0 0.0009 1.005 -0.006 0 0 0.0013 0.0027 0.996"},SMPTE240M:{BT709:"0.9993 0.0006 0.0001 0 0 -0.0004 0.9812 0.0192 0 0 -0.0034 -0.0114 1.0148",BT601:"0.913 0.0774 0.0096 0 0 -0.1051 1.1508 -0.0456 0 0 0.0063 0.0207 0.973"}},a=class e extends EventTarget{constructor(t){let s;super(),this._requests=new Set;try{if(!globalThis.Worker)throw this.destroy("Worker not supported");if(!t)throw this.destroy("No options provided");if(this._loaded=new Promise(e=>{this._init=e}),s=e._test(),this._onDemandRender="requestVideoFrameCallback"in HTMLVideoElement.prototype&&(t.onDemandRender??!0),this._offscreenRender="transferControlToOffscreen"in HTMLCanvasElement.prototype&&!t.canvas&&(t.offscreenRender??!0),this.timeOffset=t.timeOffset||0,this._video=t.video,this._videoHeight=0,this._videoWidth=0,this._videoColorSpace=null,this._canvas=t.canvas,this._video&&!this._canvas)this._canvasParent=document.createElement("div"),this._canvasParent.className="JASSUB",this._canvasParent.style.position="relative",this._canvas=this._createCanvas(),this._video.insertAdjacentElement("afterend",this._canvasParent);else if(!this._canvas)throw this.destroy("Don't know where to render: you should give video or canvas in options.");if(this._bufferCanvas=document.createElement("canvas"),this._bufferCtx=this._bufferCanvas.getContext("2d"),!this._bufferCtx)throw this.destroy("Canvas rendering not supported");this._canvasctrl=this._offscreenRender?this._canvas.transferControlToOffscreen():this._canvas,this._ctx=!this._offscreenRender&&this._canvasctrl.getContext("2d"),this._lastRenderTime=0,this.debug=!!t.debug,this.prescaleFactor=t.prescaleFactor||1,this.prescaleHeightLimit=t.prescaleHeightLimit||1080,this.maxRenderHeight=t.maxRenderHeight||0,this._boundResize=this.resize.bind(this),this._boundTimeUpdate=this._timeupdate.bind(this),this._boundSetRate=()=>{this._destroyed||this.setRate(this._video.playbackRate)},this._boundUpdateColorSpace=this._updateColorSpace.bind(this),this._video&&this.setVideo(t.video),this._onDemandRender&&(this.busy=!1,this._lastDemandTime=null),this._worker=new Worker(t.workerUrl||"jassub-worker.js"),this._worker.onmessage=e=>this._onmessage(e),this._worker.onerror=e=>this._error(e),s.then(()=>{this._destroyed||this._worker.postMessage({target:"init",wasmUrl:e._supportsSIMD&&t.modernWasmUrl?t.modernWasmUrl:t.wasmUrl??"jassub-worker.wasm",legacyWasmUrl:t.legacyWasmUrl??"jassub-worker.wasm.js",asyncRender:typeof createImageBitmap<"u"&&(t.asyncRender??!0),onDemandRender:this._onDemandRender,width:this._canvasctrl.width||0,height:this._canvasctrl.height||0,blendMode:t.blendMode||"js",subUrl:t.subLine truncated

packages/artplayer-plugin-jassub/dist/artplayer-plugin-jassub.legacy.js

@@ -4,4 +4,4 @@
  * (c) 2017-2026 Harvey Zhao
  * Released under the MIT License.
  */
-!function(e,t){"object"===typeof exports&&"undefined"!==typeof module?module.exports=t():"function"==typeof define&&define.amd?(e.artplayerPluginJassub=t(),define(function(){return e.artplayerPluginJassub})):(e="undefined"!==typeof globalThis?globalThis:e||self).artplayerPluginJassub=t()}(this,function(){"use strict";var e=Object.defineProperty,t=Object.getOwnPropertySymbols,s=Object.prototype.hasOwnProperty,i=Object.prototype.propertyIsEnumerable,a=(t,s,i)=>s in t?e(t,s,{enumerable:!0,configurable:!0,writable:!0,value:i}):t[s]=i,r=(e,r)=>{for(var n in r||(r={}))s.call(r,n)&&a(e,n,r[n]);if(t)for(var n of t(r))i.call(r,n)&&a(e,n,r[n]);return e},n=(e,t,s)=>a(e,"symbol"!==typeof t?t+"":t,s),o=(e,t,s)=>new Promise((i,a)=>{var r=e=>{try{o(s.next(e))}catch(t){a(t)}},n=e=>{try{o(s.throw(e))}catch(t){a(t)}},o=e=>e.done?i(e.value):Promise.resolve(e.value).then(r,n);o((s=s.apply(e,t)).next())});typeof HTMLVideoElement<"u"&&!("requestVideoFrameCallback"in HTMLVideoElement.prototype)&&"getVideoPlaybackQuality"in HTMLVideoElement.prototype&&(HTMLVideoElement.prototype.requestVideoFrameCallback=function(e){Object.prototype.hasOwnProperty.call(this,"_rvfcpolyfillmap")||(this._rvfcpolyfillmap={});const t=this._rvfcpolyfillid=(this._rvfcpolyfillid||0)+1,s=performance.now(),i=this.getVideoPlaybackQuality(),a=this.currentTime,r=this.mozPresentedFrames||this.mozPaintedFrames||i.totalVideoFrames-i.droppedVideoFrames,n=(o,h)=>{if(!(t in this._rvfcpolyfillmap))return;const d=this.getVideoPlaybackQuality(),l=this.mozPresentedFrames||this.mozPaintedFrames||d.totalVideoFrames-d.droppedVideoFrames,c=l>r,_=0===r&&0===l&&0===i.totalVideoFrames&&0===i.droppedVideoFrames&&0===d.totalVideoFrames&&0===d.droppedVideoFrames&&Number.isFinite(this.currentTime)&&this.currentTime!==a&&this.readyState>=2&&!this.seeking&&h-s>=1e3/30;if(c||_){const s=this.mozFrameDelay||d.totalFrameDelay-i.totalFrameDelay||0,a=h-o;delete this._rvfcpolyfillmap[t],e(h,{presentationTime:h+1e3*s,expectedDisplayTime:h+a,width:this.videoWidth,height:this.videoHeight,mediaTime:_&&!c?Math.max(0,this.currentTime):Math.max(0,this.currentTime||0)+a/1e3,presentedFrames:l,processingDuration:s})}else this._rvfcpolyfillmap[t]=requestAnimationFrame(e=>n(h,e))};return this._rvfcpolyfillmap[t]=requestAnimationFrame(e=>n(s,e)),t},HTMLVideoElement.prototype.cancelVideoFrameCallback=function(e){const t=this._rvfcpolyfillmap;t&&e in t&&(cancelAnimationFrame(t[e]),delete t[e])});const h={bt709:"BT709",bt470bg:"BT601",smpte170m:"BT601"},d={BT601:{BT709:"1.0863 -0.0723 -0.014 0 0 0.0965 0.8451 0.0584 0 0 -0.0141 -0.0277 1.0418"},BT709:{BT601:"0.9137 0.0784 0.0079 0 0 -0.1049 1.1722 -0.0671 0 0 0.0096 0.0322 0.9582"},FCC:{BT709:"1.0873 -0.0736 -0.0137 0 0 0.0974 0.8494 0.0531 0 0 -0.0127 -0.0251 1.0378",BT601:"1.001 -0.0008 -0.0002 0 0 0.0009 1.005 -0.006 0 0 0.0013 0.0027 0.996"},SMPTE240M:{BT709:"0.9993 0.0006 0.0001 0 0 -0.0004 0.9812 0.0192 0 0 -0.0034 -0.0114 1.0148",BT601:"0.913 0.0774 0.0096 0 0 -0.1051 1.1508 -0.0456 0 0 0.0063 0.0207 0.973"}},l=class e extends EventTarget{constructor(t){var s,i;let a;super(),this._requests=new Set;try{if(!globalThis.Worker)throw this.destroy("Worker not supported");if(!t)throw this.destroy("No options provided");if(this._loaded=new Promise(e=>{this._init=e}),a=e._test(),this._onDemandRender="requestVideoFrameCallback"in HTMLVideoElement.prototype&&(null==(s=t.onDemandRender)||s),this._offscreenRender="transferControlToOffscreen"in HTMLCanvasElement.prototype&&!t.canvas&&(null==(i=t.offscreenRender)||i),this.timeOffset=t.timeOffset||0,this._video=t.video,this._videoHeight=0,this._videoWidth=0,this._videoColorSpace=null,this._canvas=t.canvas,this._video&&!this._canvas)this._canvasParent=document.createElement("div"),this._canvasParent.className="JASSUB",this._canvasParent.style.position="relative",this._canvas=this._createCanvas(),this._video.insertAdjacentElement("afterend",this._canvasParent);else if(!this._canvas)throw this.destroy("Don't know where to render: you should give video or canvas in options.");if(this._bufferCanvas=document.createElement("canvas"),this._bufferCtx=this._bufferCanvas.getContext("2d"),!this._bufferCtx)throw this.destroy("Canvas rendering not supported");this._canvasctrl=this._offscreenRender?this._canvas.transferControlToOffscreen():this._canvas,this._ctx=!this._offscreenRender&&this._canvasctrl.getContext("2d"),this._lastRenderTime=0,this.debug=!!t.debug,this.prescaleFactor=t.prescaleFactor||1,this.prescaleHeightLimit=t.prescaleHeightLimit||1080,this.maxRenderHeight=t.maxRenderHeight||0,this._boundResize=this.resize.bind(this),this._boundTimeUpdate=this._timeupdate.bind(this),this._boundSetRate=()=>{this._destroyed||this.setRate(this._video.playbackRate)},this._boundUpdateColorSpace=this._updateColorSpace.bind(this),this._video&&this.setVideo(t.video),this._onDemandRender&&(this.busy=!1,this._lastDemandTime=null),this._worker=new Worker(t.workerUrl||"jassub-worker.js"),this._worker.onmessage=e=>this._onmessage(e),this._Line truncated
+!function(e,t){"object"===typeof exports&&"undefined"!==typeof module?module.exports=t():"function"==typeof define&&define.amd?(e.artplayerPluginJassub=t(),define(function(){return e.artplayerPluginJassub})):(e="undefined"!==typeof globalThis?globalThis:e||self).artplayerPluginJassub=t()}(this,function(){"use strict";var e=Object.defineProperty,t=Object.getOwnPropertySymbols,s=Object.prototype.hasOwnProperty,i=Object.prototype.propertyIsEnumerable,a=(t,s,i)=>s in t?e(t,s,{enumerable:!0,configurable:!0,writable:!0,value:i}):t[s]=i,r=(e,r)=>{for(var n in r||(r={}))s.call(r,n)&&a(e,n,r[n]);if(t)for(var n of t(r))i.call(r,n)&&a(e,n,r[n]);return e},n=(e,t,s)=>a(e,"symbol"!==typeof t?t+"":t,s),o=(e,t,s)=>new Promise((i,a)=>{var r=e=>{try{o(s.next(e))}catch(t){a(t)}},n=e=>{try{o(s.throw(e))}catch(t){a(t)}},o=e=>e.done?i(e.value):Promise.resolve(e.value).then(r,n);o((s=s.apply(e,t)).next())});typeof HTMLVideoElement<"u"&&!("requestVideoFrameCallback"in HTMLVideoElement.prototype)&&"getVideoPlaybackQuality"in HTMLVideoElement.prototype&&(HTMLVideoElement.prototype.requestVideoFrameCallback=function(e){Object.prototype.hasOwnProperty.call(this,"_rvfcpolyfillmap")||(this._rvfcpolyfillmap={});const t=this._rvfcpolyfillid=(this._rvfcpolyfillid||0)+1,s=performance.now(),i=this.getVideoPlaybackQuality(),a=this.currentTime,r=this.mozPresentedFrames||this.mozPaintedFrames||i.totalVideoFrames-i.droppedVideoFrames,n=(o,h)=>{if(!(t in this._rvfcpolyfillmap))return;const d=this.getVideoPlaybackQuality(),l=this.mozPresentedFrames||this.mozPaintedFrames||d.totalVideoFrames-d.droppedVideoFrames,c=l>r,_=0===r&&0===l&&0===i.totalVideoFrames&&0===i.droppedVideoFrames&&0===d.totalVideoFrames&&0===d.droppedVideoFrames&&Number.isFinite(this.currentTime)&&this.currentTime!==a&&this.readyState>=2&&!this.seeking&&h-s>=1e3/30;if(c||_){const s=this.mozFrameDelay||d.totalFrameDelay-i.totalFrameDelay||0,a=h-o;delete this._rvfcpolyfillmap[t],e(h,{presentationTime:h+1e3*s,expectedDisplayTime:h+a,width:this.videoWidth,height:this.videoHeight,mediaTime:_&&!c?Math.max(0,this.currentTime):Math.max(0,this.currentTime||0)+a/1e3,presentedFrames:l,processingDuration:s})}else this._rvfcpolyfillmap[t]=requestAnimationFrame(e=>n(h,e))};return this._rvfcpolyfillmap[t]=requestAnimationFrame(e=>n(s,e)),t},HTMLVideoElement.prototype.cancelVideoFrameCallback=function(e){const t=this._rvfcpolyfillmap;t&&e in t&&(cancelAnimationFrame(t[e]),delete t[e])});const h={bt709:"BT709",bt470bg:"BT601",smpte170m:"BT601"},d={BT601:{BT709:"1.0863 -0.0723 -0.014 0 0 0.0965 0.8451 0.0584 0 0 -0.0141 -0.0277 1.0418"},BT709:{BT601:"0.9137 0.0784 0.0079 0 0 -0.1049 1.1722 -0.0671 0 0 0.0096 0.0322 0.9582"},FCC:{BT709:"1.0873 -0.0736 -0.0137 0 0 0.0974 0.8494 0.0531 0 0 -0.0127 -0.0251 1.0378",BT601:"1.001 -0.0008 -0.0002 0 0 0.0009 1.005 -0.006 0 0 0.0013 0.0027 0.996"},SMPTE240M:{BT709:"0.9993 0.0006 0.0001 0 0 -0.0004 0.9812 0.0192 0 0 -0.0034 -0.0114 1.0148",BT601:"0.913 0.0774 0.0096 0 0 -0.1051 1.1508 -0.0456 0 0 0.0063 0.0207 0.973"}},l=class e extends EventTarget{constructor(t){var s,i;let a;super(),this._requests=new Set;try{if(!globalThis.Worker)throw this.destroy("Worker not supported");if(!t)throw this.destroy("No options provided");if(this._loaded=new Promise(e=>{this._init=e}),a=e._test(),this._onDemandRender="requestVideoFrameCallback"in HTMLVideoElement.prototype&&(null==(s=t.onDemandRender)||s),this._offscreenRender="transferControlToOffscreen"in HTMLCanvasElement.prototype&&!t.canvas&&(null==(i=t.offscreenRender)||i),this.timeOffset=t.timeOffset||0,this._video=t.video,this._videoHeight=0,this._videoWidth=0,this._videoColorSpace=null,this._canvas=t.canvas,this._video&&!this._canvas)this._canvasParent=document.createElement("div"),this._canvasParent.className="JASSUB",this._canvasParent.style.position="relative",this._canvas=this._createCanvas(),this._video.insertAdjacentElement("afterend",this._canvasParent);else if(!this._canvas)throw this.destroy("Don't know where to render: you should give video or canvas in options.");if(this._bufferCanvas=document.createElement("canvas"),this._bufferCtx=this._bufferCanvas.getContext("2d"),!this._bufferCtx)throw this.destroy("Canvas rendering not supported");this._canvasctrl=this._offscreenRender?this._canvas.transferControlToOffscreen():this._canvas,this._ctx=!this._offscreenRender&&this._canvasctrl.getContext("2d"),this._lastRenderTime=0,this.debug=!!t.debug,this.prescaleFactor=t.prescaleFactor||1,this.prescaleHeightLimit=t.prescaleHeightLimit||1080,this.maxRenderHeight=t.maxRenderHeight||0,this._boundResize=this.resize.bind(this),this._boundTimeUpdate=this._timeupdate.bind(this),this._boundSetRate=()=>{this._destroyed||this.setRate(this._video.playbackRate)},this._boundUpdateColorSpace=this._updateColorSpace.bind(this),this._video&&this.setVideo(t.video),this._onDemandRender&&(this.busy=!1,this._lastDemandTime=null),this._worker=new Worker(t.workerUrl||"jassub-worker.js"),this._worker.onmessage=e=>this._onmessage(e),this._Line truncated

packages/artplayer-plugin-jassub/dist/artplayer-plugin-jassub.mjs

@@ -147,7 +147,7 @@ const _o = class _o extends EventTarget {
           // @ts-ignore
           useLocalFonts: typeof queryLocalFonts < "u" && (e.useLocalFonts ?? true),
           hasBitmapBug: _o._hasBitmapBug
-        }), this._offscreenRender === true && this.sendMessage("offscreenCanvas", null, [this._canvasctrl]);
+        });
       }).catch((error) => {
         if (!this._destroyed) this.destroy(error);
       });
@@ -581,6 +581,10 @@ const _o = class _o extends EventTarget {
   }
   _ready() {
     if (this._destroyed) return;
+    if (this._offscreenRender === true && !this._initialOffscreenSent) {
+      this._initialOffscreenSent = true;
+      this._worker.postMessage({ target: "offscreenCanvas", transferable: [this._canvasctrl] }, [this._canvasctrl]);
+    }
     this._init(), this.dispatchEvent(new CustomEvent("ready"));
   }
   /**

packages/artplayer-plugin-jassub/src/jassub.es.js

@@ -143,7 +143,7 @@ class o extends EventTarget {
         // @ts-ignore
         useLocalFonts: typeof queryLocalFonts < "u" && (e.useLocalFonts ?? !0),
         hasBitmapBug: o._hasBitmapBug
-      }), this._offscreenRender === !0 && this.sendMessage("offscreenCanvas", null, [this._canvasctrl]);
+      });
     }).catch((error) => {
       if (!this._destroyed) this.destroy(error);
     });
@@ -580,6 +580,10 @@ class o extends EventTarget {
   }
   _ready() {
     if (this._destroyed) return;
+    if (this._offscreenRender === !0 && !this._initialOffscreenSent) {
+      this._initialOffscreenSent = true;
+      this._worker.postMessage({ target: "offscreenCanvas", transferable: [this._canvasctrl] }, [this._canvasctrl]);
+    }
     this._init(), this.dispatchEvent(new CustomEvent("ready"));
   }
   /**

refactor/baselines/jassub-offscreen-patch.json

@@ -0,0 +1,11 @@
+{
+  "task": "PKG-JASSUB-08",
+  "baselineCommit": "0f3c068aae1415c2d40ede8708f02f4c5864fe7a",
+  "file": "packages/artplayer-plugin-jassub/src/jassub.es.js",
+  "originalSha256LF": "1fdcf24d206e8711348dddcb5fe7b656007a9b1d81a992bb497c6d10bd0a2cdb",
+  "patchedSha256LF": "6a96af7914f702eb7d6303b466cbe16abddd278040f60cd29f153cdf60e92cb2",
+  "patchFile": "refactor/baselines/jassub-offscreen.patch",
+  "patchSha256LF": "b6cb5c4cb3c9fab920724fa7ddfe7a6b58db68d177f720231f5823fc5bfd6dac",
+  "predecessor": "refactor/baselines/jassub-vendor-patch.json",
+  "purpose": "Transfer the initial offscreen canvas on Worker readiness before releasing queued resize/render messages; keep later reattachment behavior unchanged."
+}

refactor/baselines/jassub-offscreen.patch

@@ -0,0 +1,24 @@
+diff --git a/packages/artplayer-plugin-jassub/src/jassub.es.js b/packages/artplayer-plugin-jassub/src/jassub.es.js
+index 904b40888..6bd2bc2c6 100644
+--- a/packages/artplayer-plugin-jassub/src/jassub.es.js
++++ b/packages/artplayer-plugin-jassub/src/jassub.es.js
+@@ -143,7 +143,7 @@ class o extends EventTarget {
+         // @ts-ignore
+         useLocalFonts: typeof queryLocalFonts < "u" && (e.useLocalFonts ?? !0),
+         hasBitmapBug: o._hasBitmapBug
+-      }), this._offscreenRender === !0 && this.sendMessage("offscreenCanvas", null, [this._canvasctrl]);
++      });
+     }).catch((error) => {
+       if (!this._destroyed) this.destroy(error);
+     });
+@@ -580,6 +580,10 @@ class o extends EventTarget {
+   }
+   _ready() {
+     if (this._destroyed) return;
++    if (this._offscreenRender === !0 && !this._initialOffscreenSent) {
++      this._initialOffscreenSent = true;
++      this._worker.postMessage({ target: "offscreenCanvas", transferable: [this._canvasctrl] }, [this._canvasctrl]);
++    }
+     this._init(), this.dispatchEvent(new CustomEvent("ready"));
+   }
+   /**

refactor/changes/2026-09-14-PKG-JASSUB-08-offscreen.md

@@ -0,0 +1,78 @@
+# PKG-JASSUB-08 默认 offscreen 初始化修复
+
+## 问题与实现
+
+从 `0f3c068aae1415c2d40ede8708f02f4c5864fe7a` 开始补全 05 默认模式验收时，
+Chromium/Firefox 三个核心组合都出现真实页面异常：
+`this._ctx.clearRect is not a function`。WebKit 本机没有转移能力，默认回退路径
+三项通过。这是 3 通过/6 失败的实际结果，不是浏览器连接或媒体网络问题。
+
+Worker 消息证明初始化顺序为 init → canvas → offscreenCanvas。构造时 setVideo
+已排队 resize，等待 `_loaded`；初始画布转移后来才排队。ready 解锁时，Worker
+先执行 resize，在尚未接收画布时向主线程发回 render。主线程已选 offscreen，
+`_ctx=false`，因此空图像消息也会触发 clearRect 异常。字幕随后能够出现不能
+抵消这个未处理错误。
+
+本修复只调整初始归属交接：Worker ready 到达后先同步 postMessage 转移画布，
+再 resolve `_loaded` 并派发公开 ready。标志阻止重复 ready 转移同一画布两次。
+于是所有排队的 resize、track 和 ready 监听器消息在画布交接之后到达 Worker。
+已销毁实例仍由现有终态检查拦截。没有全局禁用 offscreen，也不静默吞掉 render
+异常；后续 hybrid detach/reattach 保持原样，其完整组合仍属 05。
+
+API-04/05/10/12：公开注册和实例方法同步返回值、选项默认、资源 URL、Worker
+载荷和文件均保留，仅修复内部消息顺序。自有 TS 与公共声明不变。无新依赖、
+锁文件、版本或运行时目标变化。JASSUB 的原始及 07 来源指纹保留，08 新增
+[独立补丁](../baselines/jassub-offscreen.patch)和[补丁记录](../baselines/jassub-offscreen-patch.json)。
+校验器沿两个已记录基线验证补丁链，核对旧补丁的实际 Git diff、新补丁可逆性和
+最终 source 指纹，不覆盖历史证据。包内 ARCHITECTURE.md 同步初始化顺序及复跑方式。
+
+## 测试和真实证据
+
+[验证记录](../baselines/jassub-offscreen-validation.json)记录本次源码/产物/测试
+指纹、失败与通过报告、原生消息顺序、像素快照和最终安装矩阵。
+
+| 验证 | 结果 |
+| --- | --- |
+| 新增六项顺序与选择测试 | 修复前 5 通过/1 失败，候选 6 通过；另五项保护重复 ready、提前销毁、显式 false、无能力和自定义 canvas |
+| 联合 JASSUB | 191 项通过，含历史缺陷基线与新的候选测试，不把全部数量当成新增修复 |
+| 源码/main/legacy | 各 74 项通过；类型未变，严格分包 TS 及 lint 通过 |
+| 默认模式 main | 9 项通过：三个浏览器 × 候选核心/实际 5.4.0/实际 5.3.1-beta.1 |
+| 默认模式 legacy + 生命周期 | 21 项通过，其中默认模式 9 项，显式主线程生命周期 12 项 |
+| main 显式主线程 + 生命周期 | 21 项通过，其中播放 9 项、生命周期 12 项 |
+| 实际安装 | 15 个当前/旧编译器矩阵通过，准确入口逐条 14 负例及无 interop 消费；核心 68 和插件 15 个打包成员与最终工作区一致 |
+
+共 51 项候选真实浏览器验证，零跳过、零重试通过。实际版本为 Windows Playwright
+Chromium 153.0.8010.12、Firefox 155.0、WebKit 26.6。前两者记录 available/selected
+均 true，WebKit 两者均 false；不能称为三个引擎都验证了 offscreen。
+
+测试读取显示画布的真实 bitmap 到独立 canvas，避免对已经转移的画布调用
+getContext；未替换 Worker、WASM、字体或视频解码。仍逐项断言字幕透明像素数量、
+seek 前后像素签名变化、播放位置、网页全屏尺寸和销毁次数，且默认能力选择必须
+与平台吻合。原六项失败保留为红色证据，新实现不以放宽页面异常检查获得通过。
+
+正常构建三格式及 docs 副本相同。main gzip 从 6,045 到 6,069 字节（+24），
+legacy 从 6,385 到 6,411（+26）。安装证据复用 04 的 runner，记录保留原 task
+字段，本次验证明确归属 08。包文档更新后才运行最终 pack，没有混用旧候选。
+
+## 复跑与后续
+
+```sh
+yarn test:jassub
+yarn test:jassub-types-package
+yarn build artplayer-plugin-jassub
+node --test test/jassub-offscreen.test.js
+node --test refactor/scripts/jassub-vendor-patch.test.mjs
+```
+
+使用固定 Node/Yarn；设置 ARTPLAYER_JASSUB_ARTIFACT 为正常 main/legacy 文件，
+ARTPLAYER_JASSUB_OFFSCREEN=default 后执行
+`yarn test:browser test/browser/jassub-native.spec.js --workers=1`。
+不设置该 offscreen 变量时仍验证显式主线程路径。每次浏览器运行后先归档共享报告。
+
+关闭 JASSUB-OFFSCREEN-01，新增独立 08 任务与提交，作为 05 的前置。05 仍未完成：
+全量切源/hybrid、错误恢复、真实设备与持续 GPU/内存释放不能由上述窗口测试证明。
+06 的分发/通知和 VENDOR-04/05 保留，所有包 major、CI/CD、三轮复盘不受影响。
+没有 push、tag 或 npm 发布。
+
+回退本 commit 并正常构建恢复 07，保留其生命周期/字幕时钟修复；补丁链校验器
+随同回退。不要对运行中的 Worker 热替换画布协议。

refactor/plan.md

@@ -2,9 +2,9 @@
 
 > 由 tasks.json 生成。请修改数据后运行 `node refactor/scripts/plan.mjs --write`，不要手改本表。
 
-基线：`40fcda6a37d0049d42e49c1e64e70d4fd9ba5f7f`。总任务 232 项，范围 22 个包及工作区/示例。
+基线：`40fcda6a37d0049d42e49c1e64e70d4fd9ba5f7f`。总任务 233 项，范围 22 个包及工作区/示例。
 
-状态：todo 62 / doing 14 / blocked 0 / done 156 / deferred 0。风险 L/M/H 表示兼容风险，不表示工期。
+状态：todo 62 / doing 14 / blocked 0 / done 157 / deferred 0。风险 L/M/H 表示兼容风险，不表示工期。
 
 前置依赖是启动条件；验收是完成条件。任务可以继续拆分，但不能复用或悄悄删除旧 ID。
 
@@ -27,7 +27,7 @@
 | artplayer-plugin-dash-control | 1.1.0 | PKG-DASH-01, PKG-DASH-02, PKG-DASH-03, PKG-DASH-04, PKG-DASH-05, PKG-DASH-06 |
 | artplayer-plugin-document-pip | 1.1.0 | PKG-DPIP-01, PKG-DPIP-02, PKG-DPIP-03, PKG-DPIP-04, PKG-DPIP-05, PKG-DPIP-06 |
 | artplayer-plugin-hls-control | 1.1.0 | PKG-HLS-01, PKG-HLS-02, PKG-HLS-03, PKG-HLS-04, PKG-HLS-SDK-01, PKG-HLS-05, PKG-HLS-06 |
-| artplayer-plugin-jassub | 1.1.0 | PKG-JASSUB-01, PKG-JASSUB-02, PKG-JASSUB-03, PKG-JASSUB-04, PKG-JASSUB-05, PKG-JASSUB-06, PKG-JASSUB-07 |
+| artplayer-plugin-jassub | 1.1.0 | PKG-JASSUB-01, PKG-JASSUB-02, PKG-JASSUB-03, PKG-JASSUB-04, PKG-JASSUB-05, PKG-JASSUB-06, PKG-JASSUB-07, PKG-JASSUB-08 |
 | artplayer-plugin-multiple-subtitles | 1.2.0 | PKG-MULTI-SUB-01, PKG-MULTI-SUB-02, PKG-MULTI-SUB-03, PKG-MULTI-SUB-04, PKG-MULTI-SUB-07, PKG-MULTI-SUB-05, PKG-MULTI-SUB-06 |
 | artplayer-plugin-vast | 1.2.0 | PKG-VAST-01, PKG-VAST-02, PKG-VAST-03, PKG-VAST-04, PKG-VAST-05, PKG-VAST-06 |
 | artplayer-plugin-vtt-thumbnail | 1.1.0 | PKG-VTT-THUMB-01, PKG-VTT-THUMB-02, PKG-VTT-THUMB-03, PKG-VTT-THUMB-04, PKG-VTT-THUMB-05, PKG-VTT-THUMB-06 |
@@ -233,9 +233,10 @@
 | PKG-JASSUB-02 | artplayer-plugin-jassub<br>建立特有行为与错误测试 | PKG-JASSUB-01, ENG-03, ENG-05 | ASS 字体、时钟/seek/倍率/resize、加载失败和销毁 | 旧版本行为可重跑，成功/失败/切源/销毁有必要断言 | H | done |
 | PKG-JASSUB-03 | artplayer-plugin-jassub<br>整理内部职责与资源 | PKG-JASSUB-02, CORE-15, CORE-16 | 仅整理自有 adapter/销毁；保留第三方文件及来源 | 结构变化和缺陷修复分开记录；原 API/事件/资源生命周期通过 | H | done |
 | PKG-JASSUB-04 | artplayer-plugin-jassub<br>迁移自有源码和公开类型 | PKG-JASSUB-03, ENG-04, ENG-06, CORE-07 | JASSUB option/instance 的兼容类型包装，vendor JS 例外记录 | 严格类型检查、旧消费样例通过；声明路径/导出和同步异步兼容 | H | done |
-| PKG-JASSUB-05 | artplayer-plugin-jassub<br>验证新旧核心和组合 | PKG-JASSUB-04, CORE-22, PKG-JASSUB-07 | 真实 worker/WASM 字幕渲染与全屏、旧核心测试 | 最终核心与原支持范围核心分别通过；设备/SDK 缺证据不能标完成 | H | todo |
+| PKG-JASSUB-05 | artplayer-plugin-jassub<br>验证新旧核心和组合 | PKG-JASSUB-04, CORE-22, PKG-JASSUB-07, PKG-JASSUB-08 | 真实 worker/WASM 字幕渲染与全屏、旧核心测试 | 最终核心与原支持范围核心分别通过；设备/SDK 缺证据不能标完成 | H | todo |
 | PKG-JASSUB-06 | artplayer-plugin-jassub<br>验证分发并同步文档 | PKG-JASSUB-05, ENG-07 | jassub.js、外部资源路径、许可和离线失败记录；接续 VENDOR-04/05 完整组件/字体通知、LGPL 源码分发核对及六份未明确字体的分发处置 | tarball 入口/资源、类型、8082 demo 和 README 一致，有回退记录；来源身份已由01冻结，完整通知和未明确字体的发布处理必须闭环，不能以来源相同替代许可结论 | H | todo |
 | PKG-JASSUB-07 | artplayer-plugin-jassub<br>修复 vendor 生命周期与字幕时钟 | PKG-JASSUB-03, PKG-JASSUB-02 | 独立记录 vendor 适配差异；幂等销毁、跨容器 setVideo、构造回滚、逐帧归属和倍率/能力边界；查询 timeout/Worker error 的缺失数据回调及每请求监听器/定时器清理（JASSUB-QUERY-01） | 保持公开真实 instance、同步方法与资源路径；保留原 vendor 来源指纹并记录每项实际补丁；候选修复正例和真实字幕/失败/时钟验证通过，未证实设备不得冒充通过 | H | done |
+| PKG-JASSUB-08 | artplayer-plugin-jassub<br>修复默认 offscreen 初始化消息顺序 | PKG-JASSUB-07 | 在释放排队绘制消息前转移初始画布；独立 vendor 补丁、默认模式原生回归和维护文档 | 保留默认能力选择、Worker/资源和公开同步 API；旧红新绿消息顺序测试及真实默认 offscreen 播放/seek/全屏通过，主线程绘制保持 | H | done |
 
 ## 5 包迁移：artplayer-plugin-danmuku-mask
 
@@ -602,3 +603,4 @@
 - PKG-DANMUKU-10: [记录](changes/2026-09-13-PKG-DANMUKU-10-heatmap-density.md) [记录](baselines/danmuku-heatmap-density-validation.json)
 - PKG-DANMUKU-11: [记录](changes/2026-09-13-PKG-DANMUKU-11-visible-lifetime.md) [记录](baselines/danmuku-lifetime-validation.json)
 - PKG-DANMUKU-12: [记录](changes/2026-09-13-PKG-DANMUKU-12-frame-sampling.md) [记录](baselines/danmuku-frame-sampling-validation.json)
+- PKG-JASSUB-08: [记录](changes/2026-09-14-PKG-JASSUB-08-offscreen.md) [记录](baselines/jassub-offscreen-validation.json) [记录](baselines/jassub-offscreen-patch.json)

refactor/progress.md

@@ -1,5 +1,17 @@
 # 进度与证据
 
+## PKG-JASSUB-08 默认 offscreen 初始化完成
+
+05 默认模式验收发现 Chromium/Firefox 六项真实页面错误；初始 canvas 消息先于
+offscreenCanvas，使 Worker 返回主线程无法绘制的 render。现在先交接画布再打开
+ready 门槛，保留原能力选择，新增六项顺序/取消/回退测试（旧 5 通过/1 失败）。
+联合 191 项、源码/main/legacy 各 74 项通过；默认 main、默认 legacy 加生命周期、
+显式主线程加生命周期共 51 项原生验证通过。15 个安装类型矩阵和最终包成员一致。
+[变更与复跑](changes/2026-09-14-PKG-JASSUB-08-offscreen.md)及
+[证据](baselines/jassub-offscreen-validation.json)保留失败与修复，关闭
+JASSUB-OFFSCREEN-01。08 独立交付；05 保留全量组合、hybrid/错误恢复/设备等验收，
+06、VENDOR-04/05、独立 major 与全局发布复盘均未完成。
+
 ## PKG-JASSUB-07 vendor 生命周期与默认字幕时钟完成
 
 独立补丁保留原上游身份，修复幂等销毁、构造回滚、跨视频帧归属、数值倍率和

refactor/risk-table.md

@@ -249,3 +249,4 @@
 | JASSUB-RATE-01 | resolved / 已复现 | Fallback ratechange sends an Event instead of numeric playbackRate | PKG-JASSUB-02, PKG-JASSUB-07 |
 | JASSUB-NATIVE-FRAME-01 | resolved / 已复现 | Windows WebKit default frame-clock path does not produce subtitle demands in actual playback | PKG-JASSUB-02, PKG-JASSUB-07, PKG-JASSUB-05 |
 | JASSUB-QUERY-01 | resolved / 已复现 | Subtitle query errors throw before calling the consumer and leave request listeners attached | PKG-JASSUB-07, PKG-JASSUB-05 |
+| JASSUB-OFFSCREEN-01 | resolved / 已复现 | Default offscreen initialization lets queued resize render before Worker canvas ownership, raising clearRect on false context | PKG-JASSUB-08, PKG-JASSUB-05 |

refactor/risks.json

@@ -5599,6 +5599,28 @@
         "test/browser/jassub-lifecycle.spec.js"
       ],
       "resolutionRationale": "Actual wrapper timeout and Worker error invoke once with the original error and clean all request listeners/timers first, including throwing user callbacks. Native CSP plain Event identity is preserved; real WASM queries still succeed. Destroy cancellation settles all pending queries after cleanup; complete error recovery remains task05."
+    },
+    {
+      "id": "JASSUB-OFFSCREEN-01",
+      "title": "Default offscreen initialization lets queued resize render before Worker canvas ownership, raising clearRect on false context",
+      "confirmation": "reproduced",
+      "status": "resolved",
+      "owners": [
+        "PKG-JASSUB-08",
+        "PKG-JASSUB-05"
+      ],
+      "evidence": [
+        "test/jassub-offscreen.test.js",
+        "test/browser/jassub-native.spec.js"
+      ],
+      "compatibleResolution": "Transfer the initial canvas after Worker readiness but before releasing queued rendering; preserve selected offscreen/default and all worker resources.",
+      "closureCriteria": "Same ordering test fails on the pre-fix artifact and passes on candidate; actual default offscreen pixels, seek/layout and teardown pass on Chromium/Firefox and capability fallback on WebKit, with main-thread regressions retained.",
+      "resolutionEvidence": [
+        "refactor/changes/2026-09-14-PKG-JASSUB-08-offscreen.md",
+        "refactor/baselines/jassub-offscreen-validation.json",
+        "test/jassub-offscreen.test.js"
+      ],
+      "resolutionRationale": "Controlled queue test reproduces pre-fix canvas-before-transfer order. Candidate transfers before opening readiness and passes actual default offscreen Chromium/Firefox playback/seek/layout; Windows WebKit default capability fallback and explicit main-thread/lifecycle regressions remain green. Full device/hybrid/error recovery remains task05."
     }
   ]
 }

refactor/scripts/jassub-vendor-patch.test.mjs

@@ -8,15 +8,21 @@ import { hash } from './releases.mjs'
 test('JASSUB local vendor patch retains its exact original, changed source and reversible patch identity', () => {
   const record = JSON.parse(fs.readFileSync('refactor/baselines/jassub-vendor-patch.json', 'utf8'))
   const original = execFileSync('git', ['show', `${record.baselineCommit}:${record.file}`], { encoding: 'utf8' }).replaceAll('\r\n', '\n')
-  const current = fs.readFileSync(record.file, 'utf8').replaceAll('\r\n', '\n')
+  const followUp = JSON.parse(fs.readFileSync('refactor/baselines/jassub-offscreen-patch.json', 'utf8'))
+  const current = execFileSync('git', ['show', `${followUp.baselineCommit}:${record.file}`], { encoding: 'utf8' }).replaceAll('\r\n', '\n')
   const patch = fs.readFileSync(record.patchFile, 'utf8').replaceAll('\r\n', '\n')
   assert.equal(hash(original), record.originalSha256LF)
   assert.equal(hash(current), record.patchedSha256LF)
   assert.equal(hash(patch), record.patchSha256LF)
   assert.notEqual(record.originalSha256LF, record.patchedSha256LF)
-  execFileSync('git', ['apply', '--check', '--reverse', '--ignore-space-change', record.patchFile], { stdio: 'pipe' })
+  const committedPatch = execFileSync('git', ['diff', '--no-ext-diff', record.baselineCommit, followUp.baselineCommit, '--', record.file], { encoding: 'utf8' }).replaceAll('\r\n', '\n')
+  assert.equal(hash(committedPatch), record.patchSha256LF)
+  assert.equal(followUp.originalSha256LF, record.patchedSha256LF)
+  assert.equal(hash(fs.readFileSync(record.file, 'utf8').replaceAll('\r\n', '\n')), followUp.patchedSha256LF)
+  assert.equal(hash(fs.readFileSync(followUp.patchFile, 'utf8').replaceAll('\r\n', '\n')), followUp.patchSha256LF)
+  execFileSync('git', ['apply', '--check', '--reverse', '--ignore-space-change', followUp.patchFile], { stdio: 'pipe' })
   const registry = JSON.parse(fs.readFileSync('refactor/third-party.json', 'utf8'))
   const group = registry.vendored.find(item => item.id === 'jassub-code-and-workers')
   assert.equal(group.localPatch.originalSha256LF, record.originalSha256LF)
-  assert.equal(group.fingerprints.find(item => item.path === record.file).sha256, record.patchedSha256LF)
+  assert.equal(group.fingerprints.find(item => item.path === record.file).sha256, followUp.patchedSha256LF)
 })

refactor/tasks.json

@@ -2496,7 +2496,8 @@
       "dependsOn": [
         "PKG-JASSUB-04",
         "CORE-22",
-        "PKG-JASSUB-07"
+        "PKG-JASSUB-07",
+        "PKG-JASSUB-08"
       ],
       "status": "todo",
       "risk": "H",
@@ -4769,6 +4770,26 @@
         "changes/2026-09-13-PKG-DANMUKU-12-frame-sampling.md",
         "baselines/danmuku-frame-sampling-validation.json"
       ]
+    },
+    {
+      "id": "PKG-JASSUB-08",
+      "phase": "5 包迁移：artplayer-plugin-jassub",
+      "title": "修复默认 offscreen 初始化消息顺序",
+      "scope": [
+        "artplayer-plugin-jassub"
+      ],
+      "dependsOn": [
+        "PKG-JASSUB-07"
+      ],
+      "status": "done",
+      "risk": "H",
+      "deliverable": "在释放排队绘制消息前转移初始画布；独立 vendor 补丁、默认模式原生回归和维护文档",
+      "acceptance": "保留默认能力选择、Worker/资源和公开同步 API；旧红新绿消息顺序测试及真实默认 offscreen 播放/seek/全屏通过，主线程绘制保持",
+      "evidence": [
+        "changes/2026-09-14-PKG-JASSUB-08-offscreen.md",
+        "baselines/jassub-offscreen-validation.json",
+        "baselines/jassub-offscreen-patch.json"
+      ]
     }
   ]
 }

refactor/third-party.json

@@ -354,7 +354,8 @@
       "owners": [
         "PKG-JASSUB-01",
         "PKG-JASSUB-06",
-        "PKG-JASSUB-07"
+        "PKG-JASSUB-07",
+        "PKG-JASSUB-08"
       ],
       "sourceStatus": "Original wrapper matched npm 1.8.8; PKG-JASSUB-07 now carries an explicitly recorded local lifecycle/clock/query patch (baselines/jassub-vendor-patch.json). Worker JS is unchanged. Both WASM binaries still exactly match Pages nightly 747e392d7f6fe7c38bbcdfe05c9ada46b0b62daf/source 6b19a04ddfbad8f9bfd3237395788dd76218841b. Original wrapper hash, unchanged binaries/fonts, pinned build and submodules remain separately recorded; no independent WASM rebuild.",
       "licenseStatus": "Matching source LICENSE and nightly COPYRIGHT identified and byte-verified; full component notice assembly, LGPL source/distribution review and full FreeType license remain PKG-JASSUB-06 gates. VENDOR-04 remains open.",
@@ -386,7 +387,7 @@
         {
           "path": "packages/artplayer-plugin-jassub/src/jassub.es.js",
           "algorithm": "sha256-lf",
-          "sha256": "1fdcf24d206e8711348dddcb5fe7b656007a9b1d81a992bb497c6d10bd0a2cdb"
+          "sha256": "6a96af7914f702eb7d6303b466cbe16abddd278040f60cd29f153cdf60e92cb2"
         },
         {
           "path": "packages/artplayer-plugin-jassub/worker/jassub-worker-modern.wasm",
@@ -408,7 +409,8 @@
         "task": "PKG-JASSUB-07",
         "record": "refactor/baselines/jassub-vendor-patch.json",
         "originalSha256LF": "b973508ade00b5b9cea2f299d49f4943003372729be7350b6938e44fddb32038",
-        "patchedSha256LF": "1fdcf24d206e8711348dddcb5fe7b656007a9b1d81a992bb497c6d10bd0a2cdb"
+        "patchedSha256LF": "1fdcf24d206e8711348dddcb5fe7b656007a9b1d81a992bb497c6d10bd0a2cdb",
+        "followUp": "refactor/baselines/jassub-offscreen-patch.json"
       }
     },
     {

test/browser/jassub-native.spec.js

@@ -11,6 +11,7 @@ const artifact = process.env.ARTPLAYER_JASSUB_ARTIFACT
 const customCanvas = process.env.ARTPLAYER_JASSUB_CUSTOM_CANVAS === 'true'
 const code = artifact ? fs.readFileSync(artifact, 'utf8') : readMember(archive, member).toString()
 const onDemandRender = process.env.ARTPLAYER_JASSUB_ON_DEMAND !== 'false'
+const defaultOffscreen = process.env.ARTPLAYER_JASSUB_OFFSCREEN === 'default'
 const subtitles = `[Script Info]
 ScriptType: v4.00+
 PlayResX: 640
@@ -25,7 +26,7 @@ Dialogue: 0,0:00:05.00,0:00:30.00,Default,,0,0,0,,After seek with actual WASM
 `
 
 for (const core of ['candidate', 'published', 'published-5.3.1-beta.1']) {
-  test(`JASSUB ${artifact ? 'candidate artifact' : `published ${release.version}`} renders actual WASM subtitles through seek and layout with ${core} core, customCanvas=${customCanvas}`, async ({ page, context }, testInfo) => {
+  test(`JASSUB ${artifact ? 'candidate artifact' : `published ${release.version}`} renders actual WASM subtitles through seek and layout with ${core} core, customCanvas=${customCanvas}, defaultOffscreen=${defaultOffscreen}`, async ({ page, context }, testInfo) => {
     const resources = []
     const external = []
     const origin = new URL(testInfo.project.use.baseURL).origin
@@ -86,7 +87,7 @@ for (const core of ['candidate', 'published', 'published-5.3.1-beta.1']) {
       await page.locator('#play').click()
       await expect.poll(() => page.evaluate(() => window.art.currentTime)).toBeGreaterThan(0.1)
       await page.locator('#pause').click()
-      await page.evaluate(async ({ subContent, onDemandRender, customCanvas }) => {
+      await page.evaluate(async ({ subContent, onDemandRender, customCanvas, defaultOffscreen }) => {
         const register = window.artplayerPluginJassub.default || window.artplayerPluginJassub
         let canvas
         if (customCanvas) {
@@ -104,20 +105,26 @@ for (const core of ['candidate', 'published', 'published-5.3.1-beta.1']) {
           modernWasmUrl: '/assets/jassub/jassub-worker-modern.wasm',
           availableFonts: { 'liberation sans': '/assets/jassub/default.woff2' },
           fonts: ['/assets/jassub/default.woff2'],
-          offscreenRender: false,
+          ...(defaultOffscreen ? {} : { offscreenRender: false }),
           onDemandRender,
           ...(canvas ? { canvas } : {}),
         }))
         window.jassub = window.art.plugins.artplayerPluginJassub.instance
+        window.jassubNative.offscreen = { available: 'transferControlToOffscreen' in HTMLCanvasElement.prototype, selected: window.jassub._offscreenRender }
         window.jassub.addEventListener('error', event => window.jassubNative.errors.push(String(event.error)))
         await new Promise((resolve, reject) => {
           window.jassub.addEventListener('ready', resolve, { once: true })
           window.jassub.addEventListener('error', event => reject(event.error), { once: true })
         })
+        const readback = document.createElement('canvas')
         window.jassubPixels = (phase) => {
           const canvas = window.jassub._canvas
           const rect = canvas.getBoundingClientRect()
-          const pixels = canvas.getContext('2d').getImageData(0, 0, canvas.width, canvas.height).data
+          readback.width = canvas.width
+          readback.height = canvas.height
+          const context = readback.getContext('2d')
+          context.drawImage(canvas, 0, 0)
+          const pixels = context.getImageData(0, 0, readback.width, readback.height).data
           let visible = 0
           let signature = 0
           for (let i = 3; i < pixels.length; i += 4) {
@@ -134,7 +141,9 @@ for (const core of ['candidate', 'published', 'published-5.3.1-beta.1']) {
             window.jassubNative.snapshots.push(state)
           return state
         }
-      }, { subContent: subtitles, onDemandRender, customCanvas })
+      }, { subContent: subtitles, onDemandRender, customCanvas, defaultOffscreen })
+      const offscreen = await page.evaluate(() => window.jassubNative.offscreen)
+      expect(offscreen.selected).toBe(defaultOffscreen && !customCanvas && offscreen.available)
       await page.locator('#play').click()
       await expect.poll(() => page.evaluate(() => window.jassubPixels().visible)).toBeGreaterThan(100)
       const before = await page.evaluate(() => window.jassubPixels('before-seek'))
@@ -172,7 +181,7 @@ for (const core of ['candidate', 'published', 'published-5.3.1-beta.1']) {
     }
     finally {
       const state = await page.evaluate(() => window.jassubNative).catch(error => ({ unavailable: error.message }))
-      await testInfo.attach('actual-jassub-evidence', { body: JSON.stringify({ core, onDemandRender, customCanvas, source: artifact ? { artifact, sha256: hash(code) } : { version: release.version, integrity: release.integrity, member, sha256: hash(code) }, subtitleSha256: hash(subtitles), resources, external, state, limitation: 'Actual worker, WASM and local font with offscreenRender=false. No default offscreen path, failure recovery or device acceptance; candidate adds direct-then-host destruction.' }, null, 2), contentType: 'application/json' })
+      await testInfo.attach('actual-jassub-evidence', { body: JSON.stringify({ core, onDemandRender, customCanvas, defaultOffscreen, source: artifact ? { artifact, sha256: hash(code) } : { version: release.version, integrity: release.integrity, member, sha256: hash(code) }, subtitleSha256: hash(subtitles), resources, external, state, limitation: `Actual worker, WASM and local font; offscreen option ${defaultOffscreen ? 'omitted, actual capability/selection recorded' : 'explicitly false'}. Canvas pixels are read from a separate canvas copying the native display bitmap. No full failure recovery, sustained GPU/memory or physical-device acceptance; candidate adds direct-then-host destruction.` }, null, 2), contentType: 'application/json' })
       if (!page.isClosed()) {
         await page.evaluate(() => {
           if (window.art && !window.art.isDestroy)

test/jassub-offscreen.test.js

@@ -0,0 +1,69 @@
+import assert from 'node:assert/strict'
+// eslint-disable-next-line test/no-import-node-test -- Offscreen protocol ordering needs deterministic queue coverage.
+import test from 'node:test'
+import { jassubCandidate, jassubEnvironment } from './helpers/jassub.js'
+
+const candidate = await jassubCandidate()
+function environment(offscreen = true) {
+  const code = `${candidate.code}\nObject.defineProperty(module.exports.default || module.exports, '__canvasClass', { value: HTMLCanvasElement });`
+  const env = jassubEnvironment({ ...candidate, code })
+  const transferred = []
+  if (offscreen) {
+    env.factory.__canvasClass.prototype.transferControlToOffscreen = function () {
+      const canvas = { width: this.width, height: this.height }
+      transferred.push(canvas)
+      return canvas
+    }
+  }
+  return { ...env, transferred }
+}
+
+test('JASSUB initializes offscreen ownership before queued resize, track and ready-listener messages', async () => {
+  const env = environment()
+  const { instance } = env.factory()(env.art)
+  instance.resize(640, 360)
+  instance.setTrack('[Script Info]')
+  instance.addEventListener('ready', () => instance.resize(320, 180))
+  await env.ready()
+  const messages = env.workers[0].messages
+  assert.deepEqual(messages.slice(0, 2).map(message => message.target), ['init', 'offscreenCanvas'])
+  assert.equal(messages[1].transferable[0], env.transferred[0])
+  assert(messages.slice(2).some(message => message.target === 'canvas'))
+  assert(messages.slice(2).some(message => message.target === 'setTrack'))
+  assert.equal(instance._ctx, false)
+  instance.destroy()
+})
+
+test('JASSUB duplicate readiness does not transfer the initial offscreen canvas twice', async () => {
+  const env = environment()
+  const { instance } = env.factory()(env.art)
+  await env.ready()
+  await env.ready()
+  assert.equal(env.workers[0].messages.filter(message => message.target === 'offscreenCanvas').length, 1)
+  instance.destroy()
+})
+
+test('JASSUB destroy before readiness never transfers its offscreen canvas', async () => {
+  const env = environment()
+  const { instance } = env.factory()(env.art)
+  instance.destroy()
+  await env.flush()
+  instance._ready()
+  await env.flush()
+  assert.equal(env.workers[0].messages.length, 0)
+  assert.equal(env.workers[0].terminated, 1)
+})
+
+for (const option of [{ offscreenRender: false }, 'unsupported', 'custom']) {
+  test(`JASSUB main-thread canvas has no initial transfer for ${JSON.stringify(option)}`, async () => {
+    const env = environment(option !== 'unsupported')
+    const options = option === 'custom' ? { canvas: env.createCanvas() } : typeof option === 'object' ? option : {}
+    const { instance } = env.factory(options)(env.art)
+    await env.ready()
+    instance.resize(640, 360)
+    await env.flush()
+    assert.equal(env.workers[0].messages.some(message => message.target === 'offscreenCanvas'), false)
+    assert.equal(instance._ctx, instance._canvas.context)
+    instance.destroy()
+  })
+}