ffdshow tryouts project: Discussion & Development

[nevcairiel]

I wonder anyway why the sample rate is used for the SPDIF media type - its sample rate is independent of the actual stream sample rate.

[clsid]

A quick and dirty fix could be adding sample rate check in TsampleFormat::createMediaTypeSPDIF. But I don't have the hardware to test. One of the other devs has to fix this.

[blah123]

I dont' know, what this matter is problem with, but I think it has strong connection with ffdshow... I'll call it "sudden artifacts".
I try to encode MPEG-TS AVC/H264 to AVI XviD (recording from DVB, interlaced). I tried MeGUI and StaxRip - these two apps gives the same bug.
This is Win7 x64 and installed: ffdshow x86 (based on libvacodec), Haali, LAV x86&64, XviD.
Like I've written - this is interlaced DVB-T recording, so I use "Linear blending" deinterlacing in ffdshow. After re-encoding and playing AVI or using the option from StaxRip to preview in deafult system player, sudden artifacts appear very often in it, sometimes in 1 minute.

You can see them here (3 frames in a row, the second with macroblocs):



These artifacts aren't always in the same frames, but they change their positions. After I re-open the file, artifacts are in different frames.
I don't know, how to resolve this problem.

Couple of details about this MPEG: it hasn't WSS (resolution: simple 720x576), but it's 16:9 letterbox - so I needed to crop letterboxes, and then put in 16/9 LanczosResize (624x352).

[jmone]

Originally Posted by clsid

That is not because of the integration. A recent fix in the FFmpeg/Libav code is the cause of this performance regression. One of the devs has been notified, so hopefully the situation can be improved.

FYI, It is not just interlaced material my AVC/264 1080/50p stuff also stutters now even on an i7-920 (same with LAVVideo)

[nevcairiel]

Originally Posted by jmone

FYI, It is not just interlaced material my AVC/264 1080/50p stuff also stutters now even on an i7-920 (same with LAVVideo)

I can play 1080p/60 high-bitrate material just fine on my i7-2600k. Granted, its faster then a 920, but still, the "birds" killer sample, or the CrowdRun 2160p sample are the most complex H264 clips i really know, and they play fluently. Maybe i should benchmark them.

There must be some other factor involved that is hidden somewhere.
Did someone ever link a clip that very obviously shows the performance problem?

[jmone]

Here is a sample AVC 1080/50p file that used to without ffdshow breaking a sweat with ffmpeg-mt, now it is all dropped frames with madVR (OK on EVR) as the queues are never full. http://www.megaupload.com/?d=7JIIQC7C

[nevcairiel]

I just benchmarked that sample, and it topped out at around 80fps, which really isn't fast. In comparison, the very complex high-bitrate Birds sample still runs at around 340fps.

[jmone]

Thanks nevcairiel - I'm not sure what that all means (is more better or worse?) - I have never had issues with it prior and it really is not taxing. All I know is if I use a current version of FFDSHOW then madVR drops frames, roll back to V3882 (13 June) and it plays fine! Looking at the CPU Thread Graph - there is also a big difference in what cores are being used.

EDIT: Should also say no probs with CUVID on a Q6600 PC.

[nevcairiel]

It looks like something in that video causes it to not multi-thread properly.
I know which change caused it, but not sure if reverting it is safe.

[jmone]

OK I went back and tried various builds:
- Last Good = ffdshow_rev3892_20110620_clsid
- First Broken = ffdshow_rev3904_20110623_clsid

I did not change any config settings between the two. 100% repeatable on my rig but please let me know if there are any other FFDSHOW settings to try though both these builds are post the ffmpeg-MT merge.

[jmone]

Originally Posted by nevcairiel

It looks like something in that video causes it to not multi-thread properly.
I know which change caused it, but not sure if reverting it is safe.

This content will become more common as it is footage straight from a Pana HS700 Video Cam (and I presume the new Sony's will also spit out the same as they share the "format").

[makakam]

Guys, I'm having this problem with Dolby True HD bitstream when using ffdshow with mpc-hc. When I play the movie from the beginning everything's fine but whenever I ffwd or shut down the player and want to pick up the movie where I left off the audio is broken, I mean I can't hear anything or there's some cracking noise. How can I fix it? Just to be clear, it's only the case with movies that contain dolby true hd, dts hd is always fine. I use ATI gpu btw. Hope someone can help me out here. Thanks in advance.

[clsid]

Support for decoding H.264 Hi10P has been committed.

The Libav patch that caused the performance regression for certain H.264 files has been reverted.

[jmone]

Originally Posted by clsid

The Libav patch that caused the performance regression for certain H.264 files has been reverted.

Thanks! - EDIT: I can confirm that the H.264 performance issues have been fixed for me in ffdshow_rev3958_20110731_clsid

[Blight]

clsid:
If you can provide a patched copy that checks the bad s/pdif values, I'll test it and report if the patch works.

[makakam]

Had to help me myself, Lav filters did the job perfectly.

[roytam1]

It seems that ffdshow doesn't support ATRC (Real's ATRAC3 FourCC) and COOK.
ATRC GUID from MPC RealMedia Splitter: {4B4F4F43-0000-0010-8000-00AA00389B71}
ATRC GUID from LAV Splitter: {6B6F6F63-0000-0010-8000-00AA00389B71}

COOK GUID from MPC RealMedia Splitter: {4B4F4F43-0000-0010-8000-00AA00389B71}
COOK GUID from LAV Splitter: {6B6F6F63-0000-0010-8000-00AA00389B71}

[clsid]

Blight, roytam1

Try this test build:
http://www.mediafire.com/download.php?vxq5ud5h6zioeik

[roytam1]

Originally Posted by clsid

Blight, roytam1

Try this test build:
http://www.mediafire.com/download.php?vxq5ud5h6zioeik

It works for ATRC.
But it not work for cook from LAV Splitter. Sample: http://roy.orz.hm/samples/rv30_chroma_drift.rm

And ffdshow crash with this sample:
http://roy.orz.hm/samples/rv20_cook_...r_plus_8.51.rm

[clsid]

You should use LAV Audio/Video for realmedia. That works better than ffdshow, and it is unlikely that things will get better in ffdshow.