appendBuffer() 未追加到 sourceBuffer 中

Dun*_*ick 5 javascript buffer stream fetch media-source

我正在fetch()从 API 获取视频。

response.body是一个可读的流。所以我把它读进了reader.

然后将所有块 ( value) 推入块数组 ( chunks.push(value)) 中。

然后,块数组被转换为 arrayBuffer ( let buffer = await blob.arrayBuffer()),因为 blob 无法附加到 sourceBuffer。

以上所有步骤均正确运行!我唯一的问题是将缓冲区附加到 sourceBuffer ( sourceBuffer.appendBuffer(buffer)) 中。

控制台没有弹出错误,但 sourceBuffer 没有更新。它保持空着。

有人知道发生了什么事吗?

多谢

<body>
<video id="test-video-api">
</video>
<script>

    const fetchUrl = "https://myserver/api/video?fuid=12345";
    const videoTag = document.getElementById("test-video-api");

    function getVideo(){
        if (window.MediaSource) {
            var mediaSource = new MediaSource();
            videoTag.src = URL.createObjectURL(mediaSource);
            mediaSource.addEventListener('sourceopen', sourceOpen);
        } else {
            console.log("The Media Source Extensions API is not supported.")
        }

        async function sourceOpen(e) {
            URL.revokeObjectURL(videoTag.src);
            const mimeCodec = 'video/mp4; codecs="avc1.4d400d,mp4a.40.2"; profiles="isom,iso2,avc1,mp41"';
            var mediaSource = e.target;
            var sourceBuffer = mediaSource.addSourceBuffer(mimeCodec);
            let chunks = [];
            let response = await fetch(fetchUrl, {method: "GET", credentials: "include"});
            const reader = response.body.getReader();
            while (true){
                const {done, value} = await reader.read();
                chunks.push(value);
                if(done){
                    let blob = new Blob(chunks);
                    let buffer = await blob.arrayBuffer();
                    sourceBuffer.appendBuffer(buffer);
                    break
                }
            }
        }
    }

    getVideo()

</script>
</body>
Run Code Online (Sandbox Code Playgroud)

Duk*_*gal 0

可能您需要等待缓冲区完成更新

还有 chunks.push(value); 如果(完成)之后

    while (true) {
        const {done, value} = await reader.read();
        if (done) {
            let blob = new Blob(chunks);
            let buffer = await blob.arrayBuffer();
            while (true) {
                if (!sourceBuffer.updating) break
                console.log('bufferupdating, so wait...')
                await new Promise(resolve => setTimeout(resolve, 50));
            }
            sourceBuffer.appendBuffer(buffer);
            while (true) {
                if (!sourceBuffer.updating) break
                console.log('buffer updating, so wait...')
                await new Promise(resolve => setTimeout(resolve, 50));
            }
            break
        }
        chunks.push(value);
        total += value.length;
        console.log(total)
    }
Run Code Online (Sandbox Code Playgroud)