Hey Michael,
any news from your side?
We did some further testing with MPEG4-2 videos and the new 5.5 kernel.
Summary:
1.) decoding of videos with a height not divisible by 16 (macroblock size) brings erroneous pixels/fragments in the top area.
2.) decoding of videos with BVOP2 (2 B-Frames) [a] results in macroblock errors [1].
3.) decoding of "static" videos with low bitrates and a GoP size > 1 results in timeouts [2].
4.) encoded videos with low bitrates and GoP size > 1 show ffmpeg errors [3] during re-encoding with a different tag (in software) [b].
ad 1.)
When running [c], the fragments are not shown.
But when the stream is stored in a file and then played (as in [d]), some of the top pixel rows are erroneous.
These fragments also occur on other videos, encoded with different software libraries.
ad 3.)
This is especially the case if the video is static and the size of a P-frame packet is low.
Can e.g. be reproduced with [e], but also happens during decoding with in software encoded videos with similar attributes.
The size of a P-frame packet of such a video is around 94 bytes. Is it possible that there is a limitation regarding minimum packet size?
ad 4.)
Did [b] with a bitrate from 100k to 2M in 25k steps and a GoP size from 1 to 16.
The following combinations result in at least P-frame errors. Some also contain I-frame errors, as can be seen in [3]:
100k: 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16
125k: 4, 5, 7, 8, 9, 10, 13, 14, 15
150k: 4, 5, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16
175k: 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16
200k: 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16
225k: 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16
250k: 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16
275k: 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16
300k: 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16
325k: 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16
350k: 2, 3, 4, 6, 7, 8, 9, 10
375k: 2, 3, 4, 5, 6, 7, 8, 10
400k: 2, 3, 4, 5, 6, 7, 9, 10, 11, 13, 15, 16
425k: 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16
450k: 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16
475k: 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15
500k: 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16
525k: 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 16
GoP size of 1 did not show any errors.
=> Point 3.) and 4.) might be related?
Also noticeable: The expected/configured bitrate strongly varies from the detected bitrate.
If you need further info or if we should take further actions, just drop us a mail.
thanks & br,
Benjamin
[a]
# create video
gst-launch-1.0 videotestsrc num-buffers=200 ! video/x-raw,width=270,height=480 ! v4l2mpeg4enc output-io-mode=4 ! avimux ! filesink location=/tmp/input.avi
# re-encode in software: SP@L1 w/ BVOP2
ffmpeg -i /tmp/input.avi -c:v mpeg4 -vtag XVID -profile:v 0 -level 1 -bf 2 /tmp/output.avi
# re-encode in software: ASP@L5 w/ BVOP2
ffmpeg -i /tmp/input.avi -c:v mpeg4 -vtag XVID -profile:v 15 -level 5 -bf 2 /tmp/output.avi
# play
gst-launch-1.0 playbin uri=file:///tmp/output.avi
================================================================
[b]
# create video
gst-launch-1.0 videotestsrc num-buffers=200 ! video/x-raw,width=270,height=480 ! v4l2mpeg4enc output-io-mode=4 extra-controls="c,video_gop_size=11,video_bitrate=100000" ! avimux ! filesink location=divx/test_100000_11.avi
# re-encode it in software with different tag
ffmpeg -i divx/test_100000_11.avi -vtag "XVID" xvid/test_100000_11.avi
================================================================
[c]
# directly insert the encoded stream into the decoder
gst-launch-1.0 videotestsrc ! video/x-raw,width=480,height=360 ! v4l2mpeg4enc output-io-mode=4 ! v4l2mpeg4dec ! videoconvert ! ximagesink
================================================================
[d]
# store in avi file
gst-launch-1.0 videotestsrc num-buffers=200 ! video/x-raw,width=270,height=480 ! v4l2mpeg4enc output-io-mode=4 ! avimux ! filesink location=/tmp/input.avi
# convert tag in software, since gstreamer decoder plugin doesn't take DIVX tag but avimux plugin forces it
ffmpeg -i /tmp/input.avi -vtag "XVID" /tmp/output.avi
# play it
gst-launch-1.0 playbin uri=file:///tmp/output.avi
================================================================
[e]
# run a static video and try to encode, decode and then play it
gst-launch-1.0 videotestsrc num-buffers=200 pattern=blue ! video/x-raw,width=480,height=360 ! v4l2mpeg4enc output-io-mode=4 ! v4l2mpeg4dec ! videoconvert ! ximagesink
================================================================
================================================================
[1]
[853909.824215] coda 2040000.vpu: errors in 6 macroblocks
[853909.832120] coda 2040000.vpu: errors in 6 macroblocks
[853909.845459] coda 2040000.vpu: errors in 27 macroblocks
[853909.854856] coda 2040000.vpu: errors in 27 macroblocks
[853909.901550] coda 2040000.vpu: errors in 303 macroblocks
[853909.908588] coda 2040000.vpu: errors in 303 macroblocks
================================================================
[2]
[441877.923839] coda 2040000.vpu: CODA PIC_RUN timeout
[441878.963854] coda 2040000.vpu: CODA PIC_RUN timeout
[441880.003842] coda 2040000.vpu: CODA PIC_RUN timeout
[441881.043854] coda 2040000.vpu: CODA PIC_RUN timeout
[441882.093818] coda 2040000.vpu: CODA PIC_RUN timeout
[441883.123883] coda 2040000.vpu: CODA PIC_RUN timeout
[441884.173863] coda 2040000.vpu: CODA PIC_RUN timeout
[441885.203834] coda 2040000.vpu: CODA PIC_RUN timeout
================================================================
[3]
Input #0, avi, from 'divx/test_100000_11.avi':
Duration: 00:00:06.67, start: 0.000000, bitrate: 902 kb/s
Stream #0:0: Video: mpeg4 (Simple Profile) (DIVX / 0x58564944), yuv420p, 270x480 [SAR 1:1 DAR 9:16], 899 kb/s, 30 fps, 30 tbr, 30 tbn, 30 tbc
Stream mapping:
Stream #0:0 -> #0:0 (mpeg4 (native) -> mpeg4 (native))
Press [q] to stop, [?] for help
[mpeg4 @ 0x5649b529bfc0] Error at MB: 360
[mpeg4 @ 0x5649b529bfc0] concealing 227 DC, 227 AC, 227 MV errors in P frame
Output #0, avi, to 'xvid/test_100000_11.avi':
Metadata:
ISFT : Lavf58.20.100
Stream #0:0: Video: mpeg4 (XVID / 0x44495658), yuv420p, 270x480 [SAR 1:1 DAR 9:16], q=2-31, 200 kb/s, 30 fps, 30 tbn, 30 tbc
Metadata:
encoder : Lavc58.35.100 mpeg4
Side data:
cpb: bitrate max/min/avg: 0/0/200000 buffer size: 0 vbv_delay: -1
[mpeg4 @ 0x5649b529bfc0] slice end not reached but screenspace end (47 left 7E01DC, score= -6)
[mpeg4 @ 0x5649b529bfc0] concealing 510 DC, 510 AC, 510 MV errors in I frame
[mpeg4 @ 0x5649b52b2a80] slice end not reached but screenspace end (45 left 780321, score= -25)
[mpeg4 @ 0x5649b52b2a80] concealing 510 DC, 510 AC, 510 MV errors in I frame
[mpeg4 @ 0x5649b5295a00] slice end not reached but screenspace end (44 left 700DE7, score= -46)
[mpeg4 @ 0x5649b5295a00] concealing 510 DC, 510 AC, 510 MV errors in I frame
[mpeg4 @ 0x5649b529bfc0] slice end not reached but screenspace end (43 left 6796F1, score= -56)
[mpeg4 @ 0x5649b529bfc0] concealing 510 DC, 510 AC, 510 MV errors in I frame
[mpeg4 @ 0x5649b5297c40] slice end not reached but screenspace end (48 left 7F1AE9, score= -65)
[mpeg4 @ 0x5649b5297c40] concealing 510 DC, 510 AC, 510 MV errors in I frame
[mpeg4 @ 0x5649b52b2a80] slice end not reached but screenspace end (47 left 7E0095, score= -74)
[mpeg4 @ 0x5649b52b2a80] concealing 510 DC, 510 AC, 510 MV errors in I frame
[mpeg4 @ 0x5649b529bfc0] slice end not reached but screenspace end (42 left 400392, score= -102)
[mpeg4 @ 0x5649b529bfc0] concealing 510 DC, 510 AC, 510 MV errors in I frame
[mpeg4 @ 0x5649b5297c40] slice end not reached but screenspace end (46 left 7C0283, score= -164)
[mpeg4 @ 0x5649b5297c40] concealing 510 DC, 510 AC, 510 MV errors in I frame
[mpeg4 @ 0x5649b52b2a80] slice end not reached but screenspace end (42 left 68845C, score= -174)
[mpeg4 @ 0x5649b52b2a80] concealing 510 DC, 510 AC, 510 MV errors in I frame
frame= 200 fps=0.0 q=31.0 Lsize= 477kB time=00:00:06.66 bitrate= 586.2kbits/s speed=50.7x
video:467kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 2.229403%
