[mythtv] New MPEG2 commercial-cut code ready for testing

[Geoffrey Hausheer]

On 11/15/05, Bryan Mayland wrote:
> Geoffrey Hausheer wrote:
>     With debug enabled it faults in the avcodec_encode_video() function
> (specifically in the dct_quantize_SSE2 method).  Here's a backtrace from
> the thread:
> (gdb) bt
...
> #6  0xb71d022a in avcodec_encode_video (avctx=0x84555f0,
>     buf=0xffffff80 <Address 0xffffff80 out of bounds>, buf_size=614400,
>     pict=0x8140f60) at utils.c:868
> #7  0x0804c838 in MPEG2fixup::build_frame (this=0xbfa71084, pkt=0xbfa70c2c,
>     fname=0x0) at mpeg2fix.cpp:929
> #8  0x0804ce67 in MPEG2fixup::convert_to_i (this=0xbfa71084, frameNum=0,
>     numFrames=2, headPos=0) at mpeg2fix.cpp:1194
> #9  0x08050699 in MPEG2fixup::start (this=0xbfa71084) at mpeg2fix.cpp:1458
> #10 0x08051a89 in main (argc=7, argv=0xbfa72404) at mpeg2fix.cpp:1775
>
I don't understand why buf == -128  that isn't an allowed output from
malloc. Have you tried replacing the malloc with a memalign(16,
outbuf_size)?  there may be some stack corruption that is causing buf
to be invalid after the call to avccodec_encode_video
The same may go for intra_matrix.
It could be aligned (I think) via:
uint16_t intra_matrix[64] ATTR_ALIGNED(16);


> Opening /mnt/store/1015_20051108183000.mpg
> [mpeg2video @ 0xb7454f04]libavcodec: CPU flags: mmx mmxext sse sse2
> Input #0, mpeg, from '/mnt/store/1015_20051108183000.mpg':
>   Duration: N/A, bitrate: N/A
>   Stream #0.0[0x1e0], 29.97 fps: Video: mpeg2video, yuv420p, 640x480,
> 6000 kb/s
>   Stream #0.1[0x1c0]: Audio: mp2, 48000 Hz, stereo, 384 kb/s
> #0 PTS:36039 Delta: 0.000000ms queue: 11
> #1 PTS:34685 Delta: 15.044444ms queue: 2
> Mux rate: 6.49 Mbit/s
> [mpeg2video @ 0xb7454f04]libavcodec: CPU flags:
> Warning, QMAT_SHIFT is larger then 21, overflows possible
> Converting frame 0 to an I-frame ((null))
This looks normal (though I still have no idea what those QMAT_SHIFT
messages mean)

.Geoff