[FFmpeg-trac] #2246(avcodec:new): ffmpeg freezes and eats 100% CPU

[FFmpeg]

#2246: ffmpeg freezes and eats 100% CPU
-------------------------------------+-------------------------------------
             Reporter:  divan        |                     Type:  defect
               Status:  new          |                 Priority:  important
            Component:  avcodec      |                  Version:  git-
             Keywords:  freeze,      |  master
  avcodec, aac                       |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug:
 Trying to convert images+wav file into the 3gp video, ffmpeg freezes and
 eats 100% CPU. With some *.wav files it works correctly, but some causes
 this problem.
 Latest git HEAD, 1.0 version are affected. Earlier versions process these
 files correctly.

 How to reproduce:
 {{{
 % ./ffmpeg -v 9 -loglevel 99 -i ./audio.wav -f image2 -r 2 -i
 ./picture%d.jpg -acodec aac -ac 1 -ar 11025 -ab 64k -vcodec h263 -s qcif
 -r 2 -fs 307200 -strict -2 -y .pictures.3gp

 ffmpeg version 1.1.git-d11ac64 Copyright (c) 2000-2013 the FFmpeg
 developers
   built on Feb  6 2012 16:30:17 with gcc 4.1.2 (GCC) 20080704 (Red Hat
 4.1.2-44)
   configuration: --enable-static --extra-libs=-static --extra-
 cflags=--static --enable-libvpx
   libavutil      52. 17.101 / 52. 17.101
   libavcodec     54. 91.101 / 54. 91.101
   libavformat    54. 61.104 / 54. 61.104
   libavdevice    54.  3.103 / 54.  3.103
   libavfilter     3. 35.101 /  3. 35.101
   libswscale      2.  2.100 /  2.  2.100
   libswresample   0. 17.102 /  0. 17.102
 }}}

 Full log attached.

 If run the above command in gdb with ffmpeg_g and interrupt, backtrace
 shows that it freezes somewhere in aac_encode_frame function. Full bt:
 {{{
 rogram received signal SIGINT, Interrupt.
 quantize_and_encode_band_cost_ESC (s=0x9183d40, pb=0x9183d4c,
 in=0xb7f7b330, scaled=0x0, size=20,
     scale_idx=216, cb=11, lambda=1.40129846e-45, uplim=92, bits=0x0) at
 libavcodec/aaccoder.c:172
 172                         curbits++;
 (gdb) bt
 #0  quantize_and_encode_band_cost_ESC (s=0x9183d40, pb=0x9183d4c,
 in=0xb7f7b330, scaled=0x0, size=20,
     scale_idx=216, cb=11, lambda=1.40129846e-45, uplim=92, bits=0x0) at
 libavcodec/aaccoder.c:172
 #1  0x087137d9 in quantize_and_encode_band (s=0x9183d40, pb=0x9183d4c,
 in=0xb7f7b330, size=20,
     scale_idx=216, cb=11, lambda=1.40129846e-45) at
 libavcodec/aaccoder.c:270
 #2  0x086658d4 in aac_encode_frame (avctx=0x915ffa0, avpkt=0xbfc2654c,
 frame=0x91d5fa0,
     got_packet_ptr=0xbfc26690) at libavcodec/aacenc.c:430
 #3  0x0855061b in avcodec_encode_audio2 (avctx=0x915ffa0,
 avpkt=0xbfc2654c, frame=0x91d5fa0,
     got_packet_ptr=0xbfc26690) at libavcodec/utils.c:1227
 #4  0x08058e11 in reap_filters () at ffmpeg.c:640
 #5  0x08059861 in transcode_step () at ffmpeg.c:2991
 #6  0x0805c74b in transcode () at ffmpeg.c:3034
 #7  0x0805d6db in main (argc=Cannot access memory at address 0x8
 ) at ffmpeg.c:3209
 }}}

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/2246>
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