Pale Moon forum

With 27.9.4 I can run this Youtube roller-coaster video at 720P https://www.youtube.com/watch?v=9dC6uJDNf64 but PM28 b4 only keeps up with 480P. This is on 32-bit Gentoo linux running on an ancient Core2 with 3 gigs ram, and an i915 GPU. Both versions are launched with export MOZ_USE_OMTC=1. Attached are the diagnostics from about:support On the left is 27.9.4 and on the right is 28 b4

AFAIK, UXP does not support HW acceleration on Linux (yet?). However this should not prevent you from watching YT videos in HQ using MSE & WebM VP9, which will be selected automatically.

Yes, I get all blue boxes with white checkmarks. But my desktop PC can only go to 480P without stuttering/buffering on PM 28 versus 720P (actually almost 1080P) with 27.9.4.

JustOff wrote:AFAIK, UXP does not support HW acceleration on Linux (yet?). However this should not prevent you from watching YT videos in HQ using MSE & WebM VP9, which will be selected automatically.

MSE for WebM is not enabled by default on Mac and Linux.

// IsWebMForced returns true if we should enable MSE webm regardless of preferences.
// 1. If MP4/H264 isn't supported:
// * Windows XP
// * Windows Vista and Server 2008 without the optional "Platform Update Supplement"
// * N/KN editions (Europe and Korea) of Windows 7/8/8.1/10 without the
// optional "Windows Media Feature Pack"
// 2. If H264 hardware acceleration is not available.
// 3. The CPU is considered to be fast enough

I can view that video at 1080p under Linux with PM 28.0.0b4 and MSE+WebM enabled... Probably a driver issue on your end.

dinosaur wrote:I can view that video at 1080p under Linux with PM 28.0.0b4 and MSE+WebM enabled... Probably a driver issue on your end.

Remember that I'm running a 10-year-old Core2. I can only get 480p with PM 28. ON THIS SAME MACHINE PM 27 got 720p with the mainline linux build and could almost handle 1080p. An optimized PM 27 homebrew build under Gentoo linux does handle 1080p without stuttering/buffering.

Although I am not comparing with PM27 here, I get similar results with PM28 and a 3G C2D, 480 is OK, 720 & 1080 stop and buffer sometimes. Interestingly 'top' shows CPU use increases on each level but isn't maxed out, PM apparently uses a bit over 1 core on 1080 and less on 720. All the webm things are enabled in about:config. I would have just put this down to a connection speed issue otherwise.
Possibly installing some ffmpeg gstreamer package would enable the mse thing.
https://www.reddit.com/r/firefox/comments/33ewyx/webm_vp9_support_in_firefox/
But for me that didn't seem to stop the buffering.
gst-libav 1.14.2-1 [installed]
GStreamer Multimedia Framework ffmpeg Plugin

If you're not using hardware accelerated drawing and/or video decoding, don't expect video to be smooth.

Pushing everything through the CPU will make it subject to interruptions easily as other parts of the browser will take processing time too. The simple fact is that Pale Moon 28 and UXP is a lot heavier, and isn't as optimized at a code level as 27 is -- simply because we haven't had time yet to address these issues as getting a working browser is priority 1, and optimization comes later.
Even so, there's no guarantee that UXP will ever show the same performance levels -- the increased complexity may simply preclude it.

You can try to see if the skia back-end works better for your particular use case than cairo. try setting gfx.*.azure.backends to "skia" and restart the browser.

vingtzwanzig wrote:Possibly installing some ffmpeg gstreamer package would enable the mse thing.
https://www.reddit.com/r/firefox/comments/33ewyx/webm_vp9_support_in_firefox/
But for me that didn't seem to stop the buffering.
gst-libav 1.14.2-1 [installed]
GStreamer Multimedia Framework ffmpeg Plugin

That Reddit thread is 3 years old. Since then, both Firefox and Pale Moon (as of 27.1.0) have dropped gstreamer-wrapper-to-ffmpeg, and switched to talking directly to ffmpeg. http://www.palemoon.org/releasenotes-archived.shtml

27.1.0 (2017-02-09)
This is a major update with lots of development and bugfixes. It also introduces the so-called "PMkit" modules, our effort to restore compatibility with Jetpack/SDK extensions and making it possible for extension developers to convert their SDK extensions with little effort to a Pale Moon compatible format. For more details please check the PMkit documentation on the developer wiki.

Changes/Fixes:

Reworked the media back-end completely (thanks Travis!) to use FFmpeg (including support for FFmpeg v3 and MP3 playback) and our own MP4 parser, and no longer relying on gstreamer on Linux, as well as adding some improvements on Windows for media parsing and playing.

I just tried with the PM 27 latest stable 64 bit version, and if anything it was a bit worse, and I then retried 28 to check. The 1080 was buffering for longer intervals on 27.
I am pretty sure the buffering for me is from a download speed bottleneck. Using a more compressed codec would reduce this. I can play this full HD mp4 without buffering using Pale Moon if I download it, but trying to watch the link directly, it buffers:
http://www.mrbrklyn.com/movies/Shit%20B ... %20Say.mp4
(may be unsuitable for younger viewers, contains strong language )
During the buffering gaps CPU use also drops to very low levels, it is just waiting for the content I think. I don't know how to check what codec is actually being served by YouTube or how to download a 1080 copy of the rollercoaster video and play it, it may be against YouTube t&c's anyway. I wonder if vp9 or h.264 is being streamed from Youtube when you have a C2D cpu on Linux, and would the CPU be able to cope with decompressing it given that there is no HW acceleration? A fast C2D might still manage without assistance from a GPU.

VP9: Faster, better, buffer-free YouTube videos
Monday, April 6, 2015
As more people watch more high-quality videos across more screens, we need video formats that provide better resolution without increasing bandwidth usage. That’s why we started encoding YouTube videos in VP9, the open-source codec that brings HD and even 4K (2160p) quality at half the bandwidth used by other known codecs.

Thank you Walter and Moonchild for the advice, I have removed the unneeded gst-libav and it's dependencies, installed skia-sharp-1.60.2-1 and changed these in about:config to read just skia for both.
gfx.canvas.azure.backends skia,cairo
gfx.content.azure.backends cairo
While it was possibly a case of getting a good connection, I was able to view the roller coaster video at 720p using PM 28.0.0b4 without buffering for the first time.

Skia is part of our source tree -- you don't need any external libs for that.