javascript - 如何在js中无间隙地组合多个视频 block ？

Question

我有一组网址。我用 fetch 下载它们然后使用 await res.blob() 从每个响应中获取 blob .我需要将所有这些 blob 连接在一起以制作完整的视频，我尝试将每个 blob 插入一个数组并制作一个文件 new File(blobArray, "test")但是 结果在每个 blob 之间有一个间隙.
我尝试将每个 blob 保存为单独的文件并使用 ffmpeg -f concat -safe 0 -i text -c copy out3.mp4 连接它们结果是完美的。所以我知道我的 blob 是正确的，问题是我如何将它们组合在一起。
这是我的完整代码:

(async function() {
  var urlString = `
https://hls-c.udemycdn.com/2020-06-25_14-12-40-d54947f66bb66a48d9c119adf45739ad/1/hls/AVC_1920x1080_800k_AAC-HE_64k/aa0003ab30f349f2a87b8a745d2b648e18160.ts?Expires=1630841672&Signature=C-DrIcvmIGkm0s42EQRPWh6Y-aEWvnl2xu1LOIWyzgQqOe-~6E9rLtpR5Kdfz8lNdNXVFz2XyrsgSX1Dn8AUbxUM6umqxALPn57sdSUoVf5-JQce472EHX-roQTsy3SAM~IIXH3B6FHcpdce~1vdqTze~nQY2F3wbzCPyspJSEPU74~-TySj8PhHrFtYNFIsFVr4R-Pc4FF-EWy2zXzo0Av59-4VlOXqFYhmQwcm~kimWNXJpOYhghv6pVbFYzyp7x9tYLiX1~9hbTG3otmoBAJGRt7EUlZiBZhprAgMzhrPS2TezenBKXNf0qJEp-fnC5so0OykRt-TGhyRapbJoA__&Key-Pair-Id=APKAITJV77WS5ZT7262A,
https://hls-c.udemycdn.com/2020-06-25_14-12-40-d54947f66bb66a48d9c119adf45739ad/1/hls/AVC_1920x1080_800k_AAC-HE_64k/aa0003ab30f349f2a87b8a745d2b648e18161.ts?Expires=1630841672&Signature=bBVrS4brV209hRADZgPnYQICBcXWe6Ed6zwBOFdozjIR1tiuahx3YmPhM8uaxLNRqowALgylen1wQBmdK5bGm~73DQUcUUfGXQU8kIv45CW1DyHDzX-ECR3MDpzSzIYDI8ELbFXK8gmT7ELgtmdkSrL0XO0FXCVAzLrzSw6-0XAZgzBY7tZUncRum5Wb7EhYQgluO2uCquz6HZqaVA9IYoCeFWKFXvU3xE-RBqHXksWkZO01o3UNEEgnzYrRepurcdYY029~6MsHEyj5304pDlefXKrEj8mbZidvhaUKkiIjcoG15jznWPvN3WAewK3zXpLlCYhBMuDL0kOVIq5zjA__&Key-Pair-Id=APKAITJV77WS5ZT7262A,
https://hls-c.udemycdn.com/2020-06-25_14-12-40-d54947f66bb66a48d9c119adf45739ad/1/hls/AVC_1920x1080_800k_AAC-HE_64k/aa0003ab30f349f2a87b8a745d2b648e18162.ts?Expires=1630841672&Signature=a3lUizMPzmtntrapM9qLk0f~GrfnQAFNlEJEzrvFowGMZVMukqPVfloM7Z9J33ZThK7mKfRy7tiYH1KDzCT5hpRl0X-pcCvcmAmy4u8h1upKO0RJmaP1v7PVzqACPTyvDHNDy3Fh-pxhpO1ubKR2SR7gq1n1K6tX8sbogNHmo0jPnERRxtLKF618nAuGBPQVYofkNG0zvcomGRX7iN95ovn8Ql9IxmqsGLGI2HzlJq3v8L4iS6UYUpV4yhAtZxmbERACq82JcwdiMMlLlnn~SoenYttzDrTdSh-u321KqjAoD6lij6l~j-dReVWY4HTDlsCnGaw9w-eOIuEywi8DpA__&Key-Pair-Id=APKAITJV77WS5ZT7262A,
https://hls-c.udemycdn.com/2020-06-25_14-12-40-d54947f66bb66a48d9c119adf45739ad/1/hls/AVC_1920x1080_800k_AAC-HE_64k/aa0003ab30f349f2a87b8a745d2b648e18163.ts?Expires=1630841672&Signature=Q6eYIsoPFVKYjY0vVDcnMKKI3oV14xnfDLpvJdH7Z9GoNqojPRXOyITTmd6Ed1JCxmF9oAkfvdghH0Ks1-fSYL3tvu5kMuJe2sWbeKCimqHQ89JvhJ3hOfVvUBIv-QVdbGYXD9FOr8T5s~HYC5KkDrFqRorDidH04y67P175sBXMtYIwt04KzG7m17X8kbJkjsjuVhD0sZ0ewACz1OBPnxO9qLdvGsRqVtW1FmuKSnDULieqdsQGfuH1YkkVCr7H4t0B5SF77vvxYkvcr4uGRjKMPVdggg3BYQKCWHn~pEEP2~P6oJZdfwbu9wnKJnIvimXVleHYW-hPk0OWBD5JAg__&Key-Pair-Id=APKAITJV77WS5ZT7262A,
https://hls-c.udemycdn.com/2020-06-25_14-12-40-d54947f66bb66a48d9c119adf45739ad/1/hls/AVC_1920x1080_800k_AAC-HE_64k/aa0003ab30f349f2a87b8a745d2b648e18164.ts?Expires=1630841672&Signature=HItA9pW3RiIhf9pFFGm4Y8FmikCPXBfh8gxJVNSLsJ9cuDONLX3n26ZjYO2NaROwsID9YjxwlDuS9jqqe62A7vLPsAjVmL6WvCZ8a22tAihPBPM-qOSWoHS7E~3bSurc9CzkQwlOBvg01~Mjl-E2kvP-hn0FxhTPk1FAE8BrL6DIeGKsBqIdvVgHsJyTi9osDNPG~OtKRKRskAK37QcXidkiLjFMcbX6uqwmcVHEpP30fDj13wBMwx2suuJ27~ICmSH44CHCuRcKujISKbrVjbnsUw4ivA7a72hyybSTDhwZBzjj753FFy0LqSVWVFOJJY1HXEnZ4mpvax9N1lth2Q__&Key-Pair-Id=APKAITJV77WS5ZT7262A,
https://hls-c.udemycdn.com/2020-06-25_14-12-40-d54947f66bb66a48d9c119adf45739ad/1/hls/AVC_1920x1080_800k_AAC-HE_64k/aa0003ab30f349f2a87b8a745d2b648e18165.ts?Expires=1630841672&Signature=L4T1BtTtHVM7p2JqvXEXLcJDUNdm8IZ8LU-oPkKxYBwuZHXEdxOLTTrFSX-3N39c7JMWDljWNi2bLrjbjK2xa1yMB5eTjvZTjusJDPk91RW0cMB4qsTpuXR1ui~ybPe5ABoV6N4cUXj~bUQFfUURo66kH5UdC~SIKMzQx59mnATvKZfZwOizm2kEuc8qaXPi9yJmYdPGhr6qSN1~kl0NEWciOU3o-etMtFc29yrlGl~Fgj0bvCyAwLwtR4yQwKFHCJWZPiMfJky9GJB4LKcyKBFu7bkDjk2BzOveJklvIPF~tZKkd3ki~I5kfYhTL-~hEDT4i9hIfHJEF1JF1rf~bw__&Key-Pair-Id=APKAITJV77WS5ZT7262A,
https://hls-c.udemycdn.com/2020-06-25_14-12-40-d54947f66bb66a48d9c119adf45739ad/1/hls/AVC_1920x1080_800k_AAC-HE_64k/aa0003ab30f349f2a87b8a745d2b648e18166.ts?Expires=1630841672&Signature=Kzf38iYJwebZG2nzkrPSVEvqWxSc959XcvUqiMhZC1lFwZefNTMw1a5EHcUfObujy~3XQ3Yxm-Ls8CziLLvO3Vi8wEg05GB1COnFT1hxasQHID1tmMaXrKrRBZp2XZApehhOpSroJdx46Zb8qlM4JMu3lf30eBIHsbPOIsdmW1o2E9USZUMUKiG-T3feO1kjT3scDsoKcaX2cQrqE8c1oAuEy57eASgFKQcy0OGtrxDujPHLNWYmRv~CFZxHf8LCuMKBrL9OtXE7py0g9x4d4BvwzQ5XOoQ5d5JsfnT8EeH5Lqbh8crtauJb5BrUk6j9uV1MWviZi7WQzGcds6eItg__&Key-Pair-Id=APKAITJV77WS5ZT7262A,
https://hls-c.udemycdn.com/2020-06-25_14-12-40-d54947f66bb66a48d9c119adf45739ad/1/hls/AVC_1920x1080_800k_AAC-HE_64k/aa0003ab30f349f2a87b8a745d2b648e18167.ts?Expires=1630841672&Signature=Vc5mVh~J-WEG2eHhiXnsNFBI~kpCtTnwwgiihaP6Fvm1IeA7eJ0QzA5g2Tq1VADLI-B2Bl1Ss~CmSyyXQEiM~IxRVjiNs1~PpnIKm0gFD0iBgIZOS3GoS6bx4bkRiy1tEMn98~~1VGqZ4FxJxc59QOdjmwvAvUvGN01zojOHt0i61XDqjeLz~wFUR9MVh~QYskV4w5sR~THYpKqiMej6JAIVz3avhadVlE1p0P9Gel7LLo59WjFx3Da1huQzBNQ2B8l3-pQpepwbiI0vsrN09aZHLnVtu1NPeEbpG5lZMIhYLay5qQTg1d87ouDoZ8zWYl0buPu5ZL06DiBFIDDhrA__&Key-Pair-Id=APKAITJV77WS5ZT7262A,
https://hls-c.udemycdn.com/2020-06-25_14-12-40-d54947f66bb66a48d9c119adf45739ad/1/hls/AVC_1920x1080_800k_AAC-HE_64k/aa0003ab30f349f2a87b8a745d2b648e18168.ts?Expires=1630841672&Signature=QsdnxTFnRVml4yq~cbIMRDdESRoX6KH2AkCCm5J-MqW3QEr9RQU5Y7v41nKxIo~IgwI9FMoTRSk61whNyrLePlw2GXq38iK6UhlmpMkJYF3Tvj84GDckbpdqrIQLlZRJPngjx9n2eE3R8Sb7igXwIrr5dymYjEh2Hb0jkYs0~9Zfzr-pJAGoEdUr36hkGP2UXP4n~atb1cDW1hDbd8YJeUNYfKfTSPwq5~E9Te9P674pL2D~WutSM-Gk9xXMhVX7Z0VJWKQh5JWzSkrzDTc9rjTnotWJ7~kU1HqapqD2eVr3DOwI2b19Yv7FGWD3wrxtLA9A8AhkEbpaHLcuYyIS9w__&Key-Pair-Id=APKAITJV77WS5ZT7262A,
https://hls-c.udemycdn.com/2020-06-25_14-12-40-d54947f66bb66a48d9c119adf45739ad/1/hls/AVC_1920x1080_800k_AAC-HE_64k/aa0003ab30f349f2a87b8a745d2b648e18169.ts?Expires=1630841672&Signature=e-uHBmY7DMqAkrpRbtfyiRlglUU9wwLY5d2Oar44~xgQerrV~5dAa7q~Nf3V2WNyi22Bg88f4bvjYMIPMjghT4aZol7JXv1Q7VH~1xjydJfaIEXunOZzqswi4PbljlXui7W0c2c59hj~6c96bc6Iyr79x3bvylA1nnxJo2Y6a1Zus0irS7u-45BjXym27NtXrhOwpcVc2GNXhI74yqjXA-vFr1XVuHBHMQVMLTryYlStwoAUXnn7K~U88skq0ursQqpDFCmlDkgoXED~rdm7THJht9wOhkFbf2T79xsENBhPoiS56DLT7qIemBFGDUxHVeoTgZdMLXE2SVsgp-LBmQ__&Key-Pair-Id=APKAITJV77WS5ZT7262A,
https://hls-c.udemycdn.com/2020-06-25_14-12-40-d54947f66bb66a48d9c119adf45739ad/1/hls/AVC_1920x1080_800k_AAC-HE_64k/aa0003ab30f349f2a87b8a745d2b648e181610.ts?Expires=1630841672&Signature=KFxUkMZhteXsl3mSobA5Xg5~PQIztGtmgd~E1g2peja~oHMPNUWE6ihhcOEkO1M6CKXDycegq9~8xv6GqWSrRz5xntTYXNWyRT2-C0W2E79E0Fd1QLndb1~UP1uq~6z-8FbxXLIhHgCzSgaVtPxt8vFqQ1TI-Zd0j0ramKvfWu4iZiZTxEWn5d5Iaaf-LqTdgXWUKqWsr6F0czH7FZh6sI4NVmUAOOD1-sez5ALVr8GBruihB23W5E2yOWtk31KTC-M7TVf1AjwQTJurm~rWka4~~c2lCJ~~o-n~N5p38KdaReZWk2yCqHRYt7pdwpyqIAhosvsVs8Kf5AT2mQV-tQ__&Key-Pair-Id=APKAITJV77WS5ZT7262A,
https://hls-c.udemycdn.com/2020-06-25_14-12-40-d54947f66bb66a48d9c119adf45739ad/1/hls/AVC_1920x1080_800k_AAC-HE_64k/aa0003ab30f349f2a87b8a745d2b648e181611.ts?Expires=1630841672&Signature=AZuneobcwantsOflRrRO4DJzmW0JzqOcDDrB8YKIh~YbL5AuhlZV2OyN6fgUJ0~EVAqRk4h2RpUmZiD4ov8muNu3U-SHp1ksHia3d8cct7Ns485ta87Lb6GqX9yvF3qTNCTT3f5FSQeoKPmGXWPpbzUsdC7TGxNVy8M5IcdqHeoJDrOUeYOqnyQtNDrhWzFsp14YL4RqWBoiz0llpN6w-8QfaeWzCYkT~KxM0UKlPFDzeijXcNJS-tjCxUrT9CnYZ3IfMDvufDCfztd20x37rK1xSln~fuF4PLsMdrfpayY1lSPMgmLP9-~k7SiYth4qSU4CsdgY~1HTZJpUHg2AXQ__&Key-Pair-Id=APKAITJV77WS5ZT7262A,
https://hls-c.udemycdn.com/2020-06-25_14-12-40-d54947f66bb66a48d9c119adf45739ad/1/hls/AVC_1920x1080_800k_AAC-HE_64k/aa0003ab30f349f2a87b8a745d2b648e181612.ts?Expires=1630841672&Signature=Dcl1pJwVlfyN-Lqlq8RruR4t4c3l6Y~hSXPdZyLcspdg16gH-Jk78buQCD2LEniYF6xgXRVRgdLQj26lxiHJi2LiHXHV8~jKQVVrU2lnga9p48M35KdJZheJ~N6f91hsTpHEhYBBSR0TYhRcTMrh1WXstOMW5kHA01nVzq3mOpnHlDFpcHNuTslTAAouqeMXsdY6H4ta15puQcVnvqchOr-7c5dU4ZG14FtHF2WvjnMEWARWDvivOvoqQAqwPQgHm5SxJFw~qyZmIeRUG-TT9i-RXIAzSivg6vKiP2A-AomTOwGW3oFRXKLdMXSMlcd6lmQ7~b7jTi7uNX4Bhup-jQ__&Key-Pair-Id=APKAITJV77WS5ZT7262A,
`

  const urlArr = urlString.split(",")
  let blobArr = [];
  for(let url of urlArr) {
    if(url) {
      try{
        const res = await fetch(url);
        const blob = await res.blob();
        blobArr.push(blob)
      } catch (err) {
        console.log(err)
      }
    }
  }

  const newBlob = new Blob(blobArr)
  const finalFile = new File([newBlob], "test-udemy");
  const a = document.createElement("a")
  const url = URL.createObjectURL(finalFile);
  a.href = url;
  a.download = "test-udemy";
  document.body.appendChild(a);
  a.click();
  setTimeout(function() {
      document.body.removeChild(a);
      window.URL.revokeObjectURL(url);  
  }, 0); 
})()

不幸的是，链接很快就会过期，但我认为我想要做的很明显。
那么有什么方法可以在 JS 中识别 blob 并像 ffmpeg 那样流畅地创建整个视频吗？做？
提前致谢。

Answer 1

尝试像这样创建和下载 blob，您可以安全地省略文件创建:

let blob = new Blob( blobArr, {
        type: "video/mp4",//your own type here
    });
    let url = URL.createObjectURL(blob);
    let a = document.createElement("a");
    document.body.appendChild(a);
    a.style = "display: none";
    a.href = url;
    a.download = "PRUEBA.webm";//your own name here
    a.click();
    window.URL.revokeObjectURL(url);