I am trying to decode a raw g729 input stream to wav format like so: ffmpeg -loglevel debug -threads 1 -y -acodec g729 -f g729 -i pipe:0 -ar 44100 -acodec pcm_s32le -f wav pipe:1
As you can see, the raw g729 is piped to stdin and the wav output should be piped to stdout. I am seeing this output / errors in the log, and I get an empty wav file: ffmpeg version N-87327-g18821e3ba1-static http://johnvansickle.com/ffmpeg/ Copyright (c) 2000-2017 the FFmpeg developers built with gcc 6.4.0 (Debian 6.4.0-5) 20170906 configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio --cc=gcc-6 --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gray --enable-libfribidi --enable-libass --enable-libvmaf --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librubberband --enable-librtmp --enable-libsoxr --enable-libspeex --enable-libvorbis --enable-libopus --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxvid --enable-libzimg libavutil 55. 75.100 / 55. 75.100 libavcodec 57.106.101 / 57.106.101 libavformat 57. 82.100 / 57. 82.100 libavdevice 57. 8.101 / 57. 8.101 libavfilter 6.105.100 / 6.105.100 libswscale 4. 7.103 / 4. 7.103 libswresample 2. 8.100 / 2. 8.100 libpostproc 54. 6.100 / 54. 6.100 Splitting the commandline. Reading option '-loglevel' ... matched as option 'loglevel' (set logging level) with argument 'debug’. Reading option '-threads' ... matched as AVOption 'threads' with argument '1’. option '-y' ... matched as option 'y' (overwrite output files) with argument '1’. Reading option '-acodec' ... matched as option 'acodec' (force audio codec ('copy' to copy stream)) with argument 'g729’. Reading option '-f' ... matched as option 'f' (force format) with argument 'g729’. Reading option '-i' ... matched as input url with argument 'pipe:0’. Reading option '-ar' ... matched as option 'ar' (set audio sampling rate (in Hz)) with argument '44100’. Reading option '-acodec' ... matched as option 'acodec' (force audio codec ('copy' to copy stream)) with argument 'pcm_s32le’. Reading option '-f' ... matched as option 'f' (force format) with argument 'wav’. Reading option 'pipe:1' ... matched as output url. Finished splitting the commandline. Parsing a group of options: global . Applying option loglevel (set logging level) with argument debug. Applying option y (overwrite output files) with argument 1. Successfully parsed a group of options. Parsing a group of options: input url pipe:0. Applying option acodec (force audio codec ('copy' to copy stream)) with argument g729. Applying option f (force format) with argument g729. Successfully parsed a group of options. Opening an input file: pipe:0. [g729 @ 0x3e25da0] Opening 'pipe:0' for reading [pipe @ 0x3e265a0] Setting default whitelist 'crypto' [g729 @ 0x3e25da0] Before avformat_find_stream_info() pos: 0 bytes read:0 seeks:0 nb_streams:1 [g729 @ 0x3e25da0] After avformat_find_stream_info() pos: 0 bytes read:0 seeks:0 frames:0 Guessed Channel Layout for Input Stream #0.0 : mono Input #0, g729, from 'pipe:0': Duration: N/A, bitrate: 8 kb/s Stream #0:0, 0, 1/8000: Audio: g729, 8000 Hz, mono, s16 Successfully opened the file. Parsing a group of options: output url pipe:1. Applying option ar (set audio sampling rate (in Hz)) with argument 44100. Applying option acodec (force audio codec ('copy' to copy stream)) with argument pcm_s32le. Applying option f (force format) with argument wav. Successfully parsed a group of options. Opening an output file: pipe:1. [pipe @ 0x3e2aba0] Setting default whitelist ‘crypto' Successfully opened the file. Stream mapping: Stream #0:0 -> #0:0 (g729 (native) -> pcm_s32le (native)) cur_dts is invalid (this is harmless if it occurs once at the start per stream) No more output streams to write to, finishing. Finishing stream 0:0 without any data written to it. detected 8 logical cores [graph_0_in_0_0 @ 0x3e2daa0] Setting 'time_base' to value '1/8000’ [graph_0_in_0_0 @ 0x3e2daa0] Setting 'sample_rate' to value '8000’ graph_0_in_0_0 @ 0x3e2daa0] Setting 'sample_fmt' to value 's16’ [graph_0_in_0_0 @ 0x3e2daa0] Setting 'channel_layout' to value '0x4’ [graph_0_in_0_0 @ 0x3e2daa0] tb:1/8000 samplefmt:s16 samplerate:8000 chlayout:0x4 format_out_0_0 @ 0x3e25ca0] Setting 'sample_fmts' to value 's32’ [format_out_0_0 @ 0x3e25ca0] Setting 'sample_rates' to value '44100’ [format_out_0_0 @ 0x3e25ca0] auto-inserting filter 'auto_resampler_0' between the filter 'Parsed_anull_0' and the filter 'format_out_0_0' [AVFilterGraph @ 0x3e2c640] query_formats: 4 queried, 6 merged, 3 already done, 0 delayed [auto_resampler_0 @ 0x3e3fd20] [SWR @ 0x3e400c0] Using fltp internally between filters [auto_resampler_0 @ 0x3e3fd20] ch:1 chl:mono fmt:s16 r:8000Hz -> ch:1 chl:mono fmt:s32 r:44100Hz Output #0, wav, to 'pipe:1’: Metadata: ISFT : Lavf57.82.100 Stream #0:0, 0, 1/44100: Audio: pcm_s32le ([1][0][0][0] / 0x0001), 44100 Hz, mono, s32, 1411 kb/s Metadata: encoder : Lavc57.106.101 pcm_s32le size= 0kB time=00:00:00.00 bitrate=N/A speed= 0x video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown Input file #0 (pipe:0): Input stream #0:0 (audio): 0 packets read (0 bytes); 0 frames decoded (0 samples); Total: 0 packets (0 bytes) demuxed Output file #0 (pipe:1): Output stream #0:0 (audio): 0 frames encoded (0 samples); 0 packets muxed (0 bytes); Total: 0 packets (0 bytes) muxed Output file is empty, nothing was encoded (check -ss / -t / -frames parameters if used) 0 frames successfully decoded, 0 decoding errors Is there something wrong with my command? Interestingly, if I transcode to flac instead of wav, while I get similar errors, an accurate output file _is_ created in that case. Dave _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
