229611 2021-08-27 08:34:44 -0700 MediaRecorder with canvas captureStream() produces blank video 2025-02-14 13:14:23 -0800 1 1 1 Unclassified WebKit WebRTC Safari Technology Preview Unspecified Unspecified RESOLVED DUPLICATE 230613 InRadar P2 Normal --- 1 ashley webkit-unassigned 9anime.net.za ap bekeanloinse Civillainscorpion dahalls dasir48284 eric.carlson evawillms183 gesturesatellitedgg hannahlouriel hillaryrodham824 jeremywalsh4477 jerry jimmiemeyers180 jonlee kkinnunen Kongpheng.Nanthavongsa mfaoax myasiantv.org.ng pauldconlin playtimescheduler.com.co qtvtauizepyhhe ravee7777777 reg2405 seohubworker4 sifose2652 sims1234 Urgot68 viphthu1101 webkit-bug-importer wellsedith352 youennf oldest_to_newest 1788027 0 ashley 2021-08-27 08:34:44 -0700 Using MediaRecorder to record a MediaStream from the canvas captureStream() method appears to only produce a blank video in Safari 15 / TP 130 on macOS 12 beta (21A5304g). Demo URL: https://downloads.scirra.com/labs/screenrecording/ Steps to reproduce: 1. Click 'Record canvas' 2. Wait a few seconds 3. Click 'Stop recording' A video file will then be downloaded. Observed result: The video has the expected duration, but just displays all black. Expected result: Video to show canvas content that was recorded. Other notes: This appears to work correctly on iOS 14, so may be unique to macOS. Also note we have reports that a flickery video is recorded on Safari 14 on macOS, but we can't easily test that right now. Finally the 'Record screen' option - using getDisplayMedia() - appears to work correctly, so this looks like an issue specific to using MediaRecorder with canvas captureStream(). 1790176 1 webkit-bug-importer 2021-09-03 08:35:18 -0700 <rdar://problem/82724497> 1790538 2 alex 2021-09-05 06:10:55 -0700 We ran into the same problem (except with a bit more erratic behavior) when using a canvas for realtime video modification. It looks like it's not MediaRecorder specific but rather captureStream producing a bad stream. Here's a codepen that demonstrates the issue: https://codepen.io/alx-khovansky/pen/KKqgeNw It has a video source that is rendered to a canvas, which is then rendered to a different video element using captureStream. Works in Safari 14 but not in TP. 1791185 3 dahalls 2021-09-07 13:11:31 -0700 I'm also seeing this. It's captureStream generating blank video. One example is https://experiments.withgoogle.com/webcam-displacement This works on Safari 14.1.2 but not on TP 131 (both Big Sur). 1792901 4 youennf 2021-09-13 02:34:20 -0700 > It looks like it's not MediaRecorder specific but rather captureStream > producing a bad stream. Right, this is also my understanding. 1797271 5 dahalls 2021-09-25 22:49:08 -0700 Broken on Safari 15 now :( 1805721 6 jerry 2021-10-18 14:29:30 -0700 How do we get the devs to at least confirm this? This happens to the latest TP 133. 1817063 7 Kongpheng.Nanthavongsa 2021-11-19 18:40:45 -0800 Issue still reproducible on Safari version 15.1 (15612.2.9.1.30, 15612). Another way to reproduce: * Open https://webrtc.github.io/samples/src/content/capture/canvas-video/ * Using mouse, move teapot on the left side around, by holding down left-click and dragging your mouse around * Notice that teapot on the right doesn't mirror the left teapot's movement I wonder if issue is due to auto-play constraint violation. Console logs follows. MediaElementSession::clientWillBeginAutoplaying(74E6F415461C6466) state = Autoplaying HTMLMediaElement::setShouldDelayLoadEvent(74E6F415461C6466) true MediaElementSession::removeBehaviorRestriction(74E6F415461C6466) removed RequirePageConsentToLoadMedia MediaElementSession::autoplayPermitted(74E6F415461C6466) Returning FALSE because element is not visible in the viewport MediaElementSession::beginInterruption(74E6F415461C6466) state = Autoplaying, interruption type = InvisibleAutoplay, interruption count = 0 1827798 8 pauldconlin 2022-01-03 11:22:07 -0800 Adding on here that this is affecting capture for Flipgrid in Safari 15. We can fall back to a standard video element -> MediaRecorder capture, but that removes our ability to provide all of the canvas enabled effects. For a quick fix for this bug, we are just disabling capture on Safari 15. @youenn - anything else I can help provide to diagnose? 1827827 9 jonlee 2022-01-03 14:49:49 -0800 *** This bug has been marked as a duplicate of bug 230613 *** 2046719 21 ashley 2024-07-17 07:45:48 -0700 This issue was marked a duplicate of 230613 which was apparently fixed in 2022. I'm not an Apple developer, but if there are still issues you should file a new issue, I doubt anyone from Apple is going to track comments on an old and apparently already fixed issue.