Artifacts/pixelation/tearing

[DUXTUX]

Originally posted this on windows area but nobody replied.

I have always had problems with VLC. Artifacts/pixelation/tearing or whatever it's called. Some videos have more problems than others. High resolution videos seem to have more problems. Some VLC versions have more problems than others. Scrolling the video (shift + left/right arrow) and clicking the video timeline with mouse increase these problems.


Example
http://img163.imageshack.us/img163/3134 ... h37m05.png

From VLC

main debug: control type=3
main warning: received buffer in the future
mkv debug: seek request to -1 (0.006000%)
mkv debug: seek got 6673000 (0%)
main debug: Buffering 0%
main debug: Buffering 26%
main debug: Buffering 12%
main debug: Buffering 40%
main debug: Buffering 54%
main debug: Buffering 56%
main debug: End of audio preroll
main debug: Stream buffering done (330 ms in 0 ms)
main debug: End of audio preroll
main debug: End of video preroll
main debug: Received first picture
main debug: Decoder buffering done in 64 ms
main debug: End of audio preroll
main warning: PTS is out of range (-10000), dropping buffer
main warning: the mixer got a packet in the past (204333)
main warning: audio drift is too big (-149667), clearing out
main warning: the mixer got a packet in the past (33333)
main warning: the mixer got a packet in the past (12000)
main warning: mixer start isn't output start (4608)
main debug: control type=3
mkv debug: seek request to -1 (0.000000%)
mkv debug: seek got 0 (0%)
qt4 debug: Title 1
qt4 debug: Chapter: 6
main debug: Buffering 0%
qt4 debug: Title 1
qt4 debug: Chapter: 6
main debug: Buffering 27%
main debug: Buffering 14%
main debug: Buffering 41%
main debug: End of audio preroll
main debug: Buffering 55%
main debug: Buffering 56%
main debug: Buffering 69%
main debug: Buffering 83%
main debug: Stream buffering done (334 ms in 0 ms)
qt4 debug: Title 1
qt4 debug: Chapter: 6
qt4 debug: Title 1
qt4 debug: Chapter: 6
main debug: End of video preroll
main debug: Received first picture
main debug: Decoder buffering done in 108 ms
main warning: PTS is out of range (-10000), dropping buffer
main warning: PTS is out of range (-31333), dropping buffer
main warning: the mixer got a packet in the past (217667)
main warning: the mixer got a packet in the past (196334)
main warning: the mixer got a packet in the past (175001)
main warning: the mixer got a packet in the past (153667)
main warning: the mixer got a packet in the past (132334)
main warning: the mixer got a packet in the past (111001)
main warning: the mixer got a packet in the past (89667)
main warning: the mixer got a packet in the past (68334)
main warning: the mixer got a packet in the past (47001)
main warning: the mixer got a packet in the past (25667)
main warning: the mixer got a packet in the past (4334)
main warning: mixer start isn't output start (1664)
main warning: late picture skipped (49000 > -1672)
main warning: late picture skipped (7000 > -1672)
main debug: auto hidding mouse
main debug: control type=3
main warning: received buffer in the future
mkv debug: seek request to -1 (0.015000%)
mkv debug: seek got 21188000 (1%)
main debug: auto hidding mouse
main debug: Buffering 0%
main debug: Buffering 27%
main debug: Buffering 16%
main debug: Buffering 6%
main debug: Buffering 43%
main debug: Buffering 69%
main debug: Buffering 48%
main debug: Buffering 37%
main debug: End of audio preroll
main debug: Buffering 58%
main debug: Buffering 86%
main debug: Stream buffering done (442 ms in 0 ms)
main debug: End of audio preroll
main debug: End of video preroll
main debug: Received first picture
main debug: Decoder buffering done in 140 ms
main debug: End of audio preroll
main warning: the mixer got a packet in the past (85221)
main warning: audio drift is too big (-149667), clearing out
main warning: mixer start isn't output start (-24747)
main warning: audio drift is too big (-148667), clearing out
main warning: late picture skipped (5888 > -1273)
main debug: audio output is starving (205112), playing silence
main debug: control type=3
main warning: received buffer in the future
mkv debug: seek request to -1 (0.000000%)
mkv debug: seek got 0 (0%)
main debug: Buffering 0%
qt4 debug: Title 1
qt4 debug: Chapter: 6
qt4 debug: Title 1
main debug: Buffering 27%
qt4 debug: Chapter: 6
main debug: Buffering 14%
main debug: End of audio preroll
main debug: Buffering 41%
main debug: Buffering 55%
main debug: Buffering 56%
main debug: Buffering 69%
main debug: Buffering 83%
main debug: Stream buffering done (334 ms in 0 ms)
qt4 debug: Title 1
qt4 debug: Chapter: 6
qt4 debug: Title 1
qt4 debug: Chapter: 6
main debug: End of video preroll
main debug: Received first picture
main debug: Decoder buffering done in 99 ms
main warning: PTS is out of range (-10000), dropping buffer
main warning: PTS is out of range (-31333), dropping buffer
main warning: the mixer got a packet in the past (304113)
main warning: the mixer got a packet in the past (282780)
main warning: the mixer got a packet in the past (261447)
main warning: the mixer got a packet in the past (240113)
main warning: the mixer got a packet in the past (218780)
main warning: the mixer got a packet in the past (197447)
main warning: the mixer got a packet in the past (176113)
main warning: the mixer got a packet in the past (154780)
main warning: the mixer got a packet in the past (133447)
main warning: the mixer got a packet in the past (112113)
main warning: the mixer got a packet in the past (90780)
main warning: the mixer got a packet in the past (69447)
main warning: the mixer got a packet in the past (48113)
main warning: the mixer got a packet in the past (26780)
main warning: the mixer got a packet in the past (5447)
main warning: mixer start isn't output start (2091)
main warning: late picture skipped (47000 > -1474)
main warning: late picture skipped (5000 > -1474)
main debug: auto hidding mouse

From MediaInfo

General
Format : Matroska
File size : 619 MiB
Duration : 23mn 40s
Overall bit rate : 3 658 Kbps
Encoded date : UTC 2010-10-31 11:34:27
Writing application : mkvmerge v4.1.1 ('Bouncin' Back') built on Jul 3 2010 22:54:08
Writing library : libebml v1.0.0 + libmatroska v1.0.0
Cover : Yes / Yes / Yes

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L5.0
Format settings, CABAC : Yes
Format settings, ReFrames : 10 frames
Muxing mode : Container profile=Unknown@5.0
Codec ID : V_MPEG4/ISO/AVC
Duration : 23mn 38s
Nominal bit rate : 3 460 Kbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 23.976 fps
Resolution : 8 bits
Colorimetry : 4:2:0
Scan type : Progressive
Bits/(Pixel*Frame) : 0.070
Title : BD Video Track
Writing library : x264 core 98 r1649 20cbe10
Encoding settings : cabac=1 / ref=10 / deblock=1:1:1 / analyse=0x3:0x133 / me=umh / subme=10 / psy=1 / psy_rd=0.40:0.00 / mixed_ref=1 / me_range=24 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=0 / chroma_qp_offset=-2 / threads=6 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=2 / b_bias=0 / direct=1 / weightb=1 / weightp=2 / keyint=250 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=50 / rc=2pass / mbtree=1 / bitrate=3460 / ratetol=1.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / ip_ratio=1.40 / aq=1:1.00
Language : Japanese

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format version : Version 4
Format profile : LC
Format settings, SBR : No
Codec ID : A_AAC
Duration : 23mn 40s
Channel(s) : 2 channels
Channel positions : L R
Sampling rate : 48.0 KHz
Title : BD Audio Track
Language : Japanese

Text
ID : 3
Format : ASS
Codec ID : S_TEXT/ASS
Codec ID/Info : Advanced Sub Station Alpha
Title : Subtitles

Menu
00:00:00.000 : ja:Pre-OP
00:00:00.002 : ja:OP
00:01:29.005 : ja:Part 1
00:12:25.786 : ja:Part 2
00:21:49.140 : ja:ED
00:23:19.647 : ja:Preview

No other video player has these problems. At least none that I have used. I don't care if "it's fault of the video files" because VLC is the only one that can't play them properly. What can be the problem? Very often on many websites and forums, I hear people saying that it doesn't matter that much what codec pack or player one uses as long as it's not VLC. Apparently it's because of these problems.

Currently, I got only two problems with VLC. This problem and the fact that some small resolution videos start as full sized windows and when I make it so I could change the window size, it is still almost full screen size (it used to become the same size as the video).

I got:
Fully updated Windows Vista 32 Premium (no aero).
Q6600 2,4GHz 4 core processor
Radeon 5870 graphics card, more or less the latest drivers
Probably a quite new DirectX because I play lots of new games
There is no difference if the video is in SATA hard drive or non-SATA hard drive or external USB hard drive.

[JimX]

I have trouble with all of the Matroska files. I have installed the CCCP codec pack and find that the files do not play correctly in Windows Media Player either. They "catch", freeze, pixelate, etc. I am on Vista. Is there anything one can do to sacrifice resolution quality or something else so as to avoid the freezing etc?

These are the ffmpeg settings I have right now. I'm not sure what other settings I might try tweaking. Or is there something I could do in Vista settings ...?

http://www.lovenotmoney.org/ffmpeg.jpg

Any help would be HUGELY appreciated!

jim

[DUXTUX]

Hello, anyone?

I have been using VLC for a long time. VLC always had 3 big problems.

1. Subtitle support. There used to be lots of problems but with current version, they work almost perfectly. They look the way they were intended, even with effects. The only small problem is that when I click to get to some time in the video, subtitles that should have appeared just before the time I jumped won't be shown. Other players show them.

2. In some videos, when I click to get to some part of the video, it goes to wrong time. For example, if I click X, I get to Y
-------------------Y---X----------------------

3. Artifacts/pixelation/tearing. High video resolution, using shift+arrow key or clicking with mouse to get to another part, and some video formats seem to increase this problem.


Due to these 3 problems, VLC is hated by many people. In many playback guides, they say that "use anything but VLC".

[DUXTUX]

I hate to post the same thing so many times but could some developer or someone who knows stuff at least confirm that the problem has been noticed and that something will be done to fix it some day.

[TMorita]

I'm seeing the artifacts where some blocks are corrupted for a few frames.
The problem seems to occur more often when the system is slow, such as decompressing 720p video on an Atom-based laptop.

From what I know of video compression, video frames are typically encoded as two types of frames:

1. key frames, which are a compression of the entire current frame
2. differentialf rames, which are encoded as the difference between the last key frame and the current frame

What I'm guessing happens:

1. VLC is running fine decompressing video
2. Some background task kicks in, and causes VLC to run behind on decompression
3. VLC tries to catch back up, and fails to completely decompress a key frame
4. The next few video frames which are decompressed have blocks of garbage data because they are based on a key frame which has garbage data.
I typically see a few blocks (looks about 16x16 or so) which have random garbage in them.

Hope this helps you guys fix this problem.

[TMorita]

Okay, I've gotten the glitching to happen a few times.

I forced VLC to hiccup on a slow system by copying files in the background.

The glitching seems to corrupt the chroma information for a key frame and it just looks like random garbage.
It looks like subsequent differential frames contain only luminance info with no chroma.
So it looks like shadows moving on top of garbage pixels for a few frames after the glitch occurs.

[DUXTUX]

My computer is fast and I'm not running any unnecessary programs. Problem happens only with VLC.

[Meda]

@duxtux

found the problem finally - vlc can't yet handle 10 b-frames.

[Lotesdelere]

found the problem finally - vlc can't yet handle 10 b-frames.

Please upload a short sample showing this issue on some file sharing site like Megaupload or Rapidshare.

[Meda]

i encoded 2 samples , one with 8 b-frames and one with 10 b-frames. the first one plays out just fine, but the second one, when played from the beginning to the end, shows some deformation near the end

sample 1
http://www.megaupload.com/?d=ZZJKZ1C7
sample 2
http://www.megaupload.com/?d=1J06FLWC

[Lotesdelere]

Yes, confirmed.
And remuxing the file with MKVtoolnix didn't help.

However the problem does not occur with the same video stream into an MP4 container.

[Jean-Baptiste Kempf]

Then, this is a bug with 10 b-frames in MKV, right?

[Lotesdelere]

This should fix the issue:
http://git.videolan.org/?p=vlc.git;a=co ... 74ffa4bfa8

Please test the nightly build.

[TMorita]

After experiementation, I found my problem isn't related to the system load.
It seems to be a problem with the h264 decoder. Here is a file which demonstrates the problems I am seeing:

http://www.megaupload.com/?d=2AAF0PH4

Here's what I see with vlc-1.1.5:

Numerous freezes for 1-4 seconds
Weird artifacts
Then after playing the first 25 seconds of the file, it freezes for about 5 seconds, then reseeks back to the beginning

[Meda]

tested with vlc-1.2.0-git-20110117-0003, no change for "sample #2"

After experiementation, I found my problem isn't related to the system load.
It seems to be a problem with the h264 decoder. Here is a file which demonstrates the problems I am seeing:

http://www.megaupload.com/?d=2AAF0PH4

Here's what I see with vlc-1.1.5:

Numerous freezes for 1-4 seconds
Weird artifacts
Then after playing the first 25 seconds of the file, it freezes for about 5 seconds, then reseeks back to the beginning

turn off "ordered chapters" to play the whole file , and turn on GPU acceleration, it kinda helps in this case

[DUXTUX]

The same problem happens with:
Format : OGG
File size : 232 MiB
Duration : 23mn 37s
Overall bit rate : 1 373 Kbps

Video
ID : 0 (0x0)
Format : MPEG-4 Visual
Format profile : Advanced Simple@L3
Format settings, BVOP : Yes
Format settings, QPel : Yes
Format settings, GMC : No warppoints
Format settings, Matrix : Default (H.263)
Codec ID : XVID
Codec ID/Hint : XviD
Duration : 23mn 35s
Bit rate : 1 066 Kbps
Width : 640 pixels
Height : 480 pixels
Display aspect ratio : 4:3
Frame rate : 23.976 fps
Resolution : 8 bits
Colorimetry : 4:2:0
Scan type : Progressive
Bits/(Pixel*Frame) : 0.145
Stream size : 180 MiB (78%)
Writing library : XviD 0.0.12 (UTC 2003-06-11)

Audio #1
ID : 1 (0x1)
Format : Vorbis
Format settings, Floor : 1
Duration : 23mn 37s
Bit rate mode : Constant
Bit rate : 120 Kbps
Channel(s) : 2 channels
Sampling rate : 48.0 KHz
Replay gain : 1.58 dB
Stream size : 20.3 MiB (9%)
Writing library : libVorbis 1.0 (UTC 2002-07-17)

Audio #2
ID : 2 (0x2)
Format : Vorbis
Format settings, Floor : 1
Duration : 23mn 37s
Bit rate mode : Constant
Bit rate : 120 Kbps
Channel(s) : 2 channels
Sampling rate : 48.0 KHz
Replay gain : 0.92 dB
Stream size : 20.3 MiB (9%)
Writing library : libVorbis 1.0 (UTC 2002-07-17)

[DUXTUX]

So what is the problem? This happens with almost every video, avi/mkv/mp4. It happens with many video types. Usually more when the resolution is high. It happens ONLY on VLC.

[gliomarto]

turn off "ordered chapters" to play the whole file

I'm sorry for being stupid, but where do I turn it off?

[DUXTUX]

I guess nobody knows what the cause is. VLC has had this problem for years with many formats. ONLY VLC.

[Rémi Denis-Courmont]

In the case of the first post, it's even more trivial. From the codec data, this is HD video. Most CPU's cannot decode HD video fast enough, and the result is pixelization, tearing and missing frames.

And then, well, we have to live with the fact that VLC is entirely supported by volunteers, and difficult problems cannot be fixed in these conditions.

[DUXTUX]

Yeah but if it's CPU, why does it happen only on vlc?
Why does it happen with
Width : 640 pixels
Height : 480 pixels

video too?

q6600 should be fast enough. But whats strange that some old VLC versions didn't have this problem (they had lots of other problems though, especially with subtitles)
Can't remember which version. I hope someone finds out something.

[DUXTUX]

Still nothing? Come on. VLC could be so awesome.

[Cide_Que]

This is still happening on the most recent build 1.1.11 I watch a ton of stuff and I notice it all the time. The audio keeps going and it catches up eventually. KMplayer has a similar issue where it will just freeze the frame but keep the audio going and then the video will fast forward to re sync. But with VLC we see this artifacting.
My system is 6gb of ram, i7 860, 5870 ATI card, and even with NOTHING else running this still occurs. Been looking to see if you guys had fixed it yet since I've seen this issue for years.
However it sounds like you have found the problem with those b10 frames, not 100% sure what they are but if this issue were fixed I know of at least 20 people that would switch to VLC over KMplayer and classic.

Hope this can be fixed.

[Cide_Que]

Well I don't figure that they will fix this anytime soon.. since its been like this from the start.
ANYWAYS, I found a program that plays without any artifacts/pixelations/tearing. Its called Media Player Classic. install that with CCCP and you are good to go.
Works like a charm and I've already watched over 20 things on it with no problems. I do hope that VLC fixes these issues, but until then I'm sticking with Media Player Classic.
Just wanted to let anyone visiting this thread know.. I know this info would have been helpful to me long ago.