Hi All,
I bumped into segfault when trying to use the a52 plugin. I linked the plugin with the latest svn revision of ffmpeg (r9102).
Starting program: /usr/bin/aplay -Dsurround test.wav Failed to read a valid object file image from memory. [Thread debugging using libthread_db enabled] [New Thread -1211078432 (LWP 9835)] Playing WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Stereo Program received signal SIGSEGV, Segmentation fault. [Switching to Thread -1211078432 (LWP 9835)] av_crc (ctx=0x0, crc=0, buffer=0x8072c14 , length=1116) at crc.c:77 77 if(!ctx[256]) (gdb) bt #0 av_crc (ctx=0x0, crc=0, buffer=0x8072c14 , length=1116) at crc.c:77 #1 0xb78ce8a1 in output_frame_end (s=0x0) at ac3enc.c:1135 #2 0xb78d1010 in AC3_encode_frame (avctx=0x806d3c0, frame=0x8072c10 "\vw", buf_size=6136, data=0x806e400) at ac3enc.c:1261 #3 0xb7730f68 in avcodec_encode_audio (avctx=0x806d3c0, buf=0x8072c10 "\vw", buf_size=6136, samples=0x0) at utils.c:863 #4 0xb772f66c in convert_data (rec=0x805c868) at pcm_a52.c:57 #5 0xb7730101 in a52_transfer (io=0x805c868, areas=0x80551f0, offset=0, size=1536) at pcm_a52.c:197 #6 0xb7efcf11 in ioplug_priv_transfer_areas (pcm=0x806c138, areas=0x80551f0, offset=0, size=0) at pcm_ioplug.c:521 #7 0xb7efcfd6 in snd_pcm_ioplug_mmap_commit (pcm=0x806c138, offset=0, size=1536) at pcm_ioplug.c:590 #8 0xb7ebf7b7 in snd_pcm_mmap_commit (pcm=0x0, offset=0, frames=1536) at pcm.c:6305 #9 0xb7ecc7e4 in snd_pcm_plugin_write_areas (pcm=0x8054f48, areas=0xbfc8ea10, offset=0, size=1536) at pcm_plugin.c:282 #10 0xb7ebfc42 in snd_pcm_write_areas (pcm=0x8054f48, areas=0xbfc8ea10, offset=0, size=1536, func=0xb7ecc740 <snd_pcm_plugin_write_areas>) at pcm.c:6492 #11 0xb7ecbdff in snd_pcm_plugin_writei (pcm=0x8054f48, buffer=0x8074410, size=1536) at pcm_plugin.c:353 #12 0xb7eb7da5 in snd_pcm_writei (pcm=0x8068488, buffer=0x8074410, size=0) at pcm_local.h:401 #13 0x0804d05a in pcm_write (data=0x8074410 "", count=1536) at aplay.c:1260 #14 0x0804d66f in playback_go (fd=8, loaded=0, count=48457728, rtype=2, name=0xbfc8fa1d "test.wav") at aplay.c:1986 #15 0x0804e9b2 in playback (name=0xbfc8fa1d "test.wav") at aplay.c:2044 #16 0x08050ea9 in main (argc=3, argv=0xbfc8ed64) at aplay.c:601
The patch below fixes this segmentation fault by adding a call to avcodec_init()
diff -Naur alsa-plugins-1.0.13/a52/pcm_a52.c alsa-plugins-1.0.13-patched/a52/pcm_a52.c --- alsa-plugins-1.0.13/a52/pcm_a52.c 2006-09-29 13:51:37.000000000 +0200 +++ alsa-plugins-1.0.13-patched/a52/pcm_a52.c 2007-05-22 18:49:56.000000000 +0200 @@ -676,6 +676,7 @@ rec->channels = channels; rec->format = format;
+ avcodec_init(); avcodec_register_all(); rec->codec = avcodec_find_encoder(CODEC_ID_AC3); if (! rec->codec) {
Regards, Fabian