[MPlayer-dev-eng] lavcac3enc broken?

[eatdirt]

I will, and also try to inquire the code. But, in the meanwhile, to 
confirm it is coming from the patches, I actually tested without, and no 
sigsegv in that case.

I've also found another issue with the patches, tested with an eac3 
stream, the ac3 output sound is actually slightly corrupted. There is a 
noise sounding like a "cricket" in the background of the actual sound 
track. The volume of that "cricket" is at about something like 5-10% of 
the track's volume, and seems to be louder when the audio is dominated 
by low frequencies.

Cheers,
Chris.

On 05/04/2023 20:47, Reimar Döffinger wrote:
> 
> 
>> On 4 Apr 2023, at 22:09, eatdirt <eatdirt at protonmail.com> wrote:
>>
>> Indeed, that was a SIGFPE!
>>
>> That second patch on top on the first works, well done! Well, it "almost" works :)
>>
>> It seems to trigger a SIGSEGV when -lavdopts threads=n is set, but if this option is not set, the audio stream is well converted to ac3 with the proper number of channels! Sorry to have found that, it was on the chain of my default options.
>>
>> With -lavdopts threads=something
> 
> I don't really see how that would be related, it's for decoding and SHOULD not affect this part.
> Can you try to get debug symbols for your FFmpeg and run in valgrind?
> 
>>
>> Thread 1 "mplayer" received signal SIGSEGV, Segmentation fault.
>> 0x00007ffff6352dbf in ff_ac3_validate_metadata () from /lib64/libavcodec.so.59
>>
>> #0  0x00007ffff6352dbf in ff_ac3_validate_metadata () at /lib64/libavcodec.so.59
>> #1  0x00007ffff6354f62 in ff_ac3_fixed_encode_frame () at /lib64/libavcodec.so.59
>> #2  0x00007ffff64abcfa in encode_receive_packet_internal () at /lib64/libavcodec.so.59
>> #3  0x00007ffff64ac324 in avcodec_send_frame () at /lib64/libavcodec.so.59
>> #4  0x000055555574518d in lavc_encode_audio (ctx=0x555556701040, src=0x55555677a700, src_len=36864, dst=dst at entry=0x5555567746f8, dst_len=dst_len at entry=24576) at av_helpers.c:157
>> #5  0x0000555555745822 in play (af=<optimized out>, data=<optimized out>) at libaf/af_lavcac3enc.c:244
>> #6  0x000055555567f416 in af_play (s=<optimized out>, data=<optimized out>, data at entry=0x7fffffffc600) at libaf/af.c:584
>> #7  0x000055555569161b in filter_n_bytes (len=130944, sh=0x555555b80da0) at libmpcodecs/dec_audio.c:423
>> #8  mp_decode_audio (sh_audio=sh_audio at entry=0x555555b80da0, minlen=minlen at entry=96000) at libmpcodecs/dec_audio.c:493
>> #9  0x00005555555e3a4a in fill_audio_out_buffers () at mplayer.c:2164
>> #10 main (argc=<optimized out>, argv=<optimized out>) at mplayer.c:3777