HTML5 record moderate video quality for upload to be playable by Safari -


i creating web-based mobile app should possible upload video-recordings. there 2 ways achieve this:

use input:

<input type="file" name="video" accept="video/*" capture></input>

use rtc mediarecorder: 

var recordedblobs = []; function handledataavailable(event) {     if (event.data && event.data.size > 0) {         recordedblobs.push(event.data);     } }  var options = {     mimetype: 'video/webm',     audiobitspersecond : 128000,     videobitspersecond : 2500000 }  mediarecorder = new mediarecorder(window.stream, options); mediarecorder.ondataavailable = handledataavailable; mediarecorder.start(10);

while first option works main problem uses build-in mobile camera application leaving no control on quality, again leads potentially large files (especially on android)

second version gives full control on quality , lets os create moderate file sizes size-wise acceptable content in application. ios/safari not support feature yet, ok since iphones record small files default when started browser. can activate option 1 when user-agent ios.

now problems:

first option fine if could:

  1. control video recording quality of mobile application
  2. post-elaborate recording change resolution before upload

the problem option 2 .webm container type supported, , safari not support type.

so i'm little stuck - right seems option post-convert incoming .webm files .mp4 on server uploaded. seems cpu costly process on server.

any ideas?

you can record h.264 webm container. supported chrome.

var options = {mimetype: 'video/webm;codecs=h264'};  media_recorder = new mediarecorder(stream, options);

although usual combination of video format , container - valid.

now change h.264/webm h.264/mp4 without transcoding video stream using ffmepg (-vcodec copy).

you try re-wrapping webm mp4 client side in javascript using ffmpeg.js.


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