I also wanted to share my full debug-level log from FFMPEG when I try to
record ALSA audio, below. I have a few questions:
1. Why is my ALSA duration a *negative* value?
2. My ALSA bitrate is shown as 3072 kbps. This seems high - I only have a
Pi Zero. Is this a value I can manually set?
$ ALSA_CONFIG_PATH=/usr/share/alsa/alsa.conf:./dumpasoundrc
/home/pi/special/ffmpeg/ffmpeg -v 9 -loglevel 99 -f alsa -acodec pcm_s32le
-i michooks -f null -
ffmpeg version git-2017-02-05-e57fd92 Copyright (c) 2000-2017 the FFmpeg
developers
built with gcc 4.9.2 (Raspbian 4.9.2-10)
configuration: --extra-cflags=-I/opt/vc/include/IL --enable-nonfree
--enable-omx-rpi --logfile=CONFIG.TXT
libavutil 55. 46.100 / 55. 46.100
libavcodec 57. 75.100 / 57. 75.100
libavformat 57. 66.101 / 57. 66.101
libavdevice 57. 2.100 / 57. 2.100
libavfilter 6. 73.100 / 6. 73.100
libswscale 4. 3.101 / 4. 3.101
libswresample 2. 4.100 / 2. 4.100
Splitting the commandline.
Reading option '-v' ... matched as option 'v' (set logging level) with
argument '9'.
Reading option '-loglevel' ... matched as option 'loglevel' (set logging
level) with argument '99'.
Reading option '-f' ... matched as option 'f' (force format) with argument
'alsa'.
Reading option '-acodec' ... matched as option 'acodec' (force audio codec
('copy' to copy stream)) with argument 'pcm_s32le'.
Reading option '-i' ... matched as input url with argument 'michooks'.
Reading option '-f' ... matched as option 'f' (force format) with argument
'null'.
Reading option '-' ... matched as output url.
Finished splitting the commandline.
Parsing a group of options: global .
Applying option v (set logging level) with argument 9.
Successfully parsed a group of options.
Parsing a group of options: input url michooks.
Applying option f (force format) with argument alsa.
Applying option acodec (force audio codec ('copy' to copy stream)) with
argument pcm_s32le.
Successfully parsed a group of options.
Opening an input file: michooks.
[ALSA Debug Hook] Installing hooks.
Hooks PCM
Slave: Soft volume PCM
Control: Boost Capture Volume
min_dB: -3
max_dB: 50
resolution: 256
Slave: Route conversion PCM
Transformation table:
0 <- 0
1 <- 0
Slave: Mmap emulation PCM
Slave: Hardware PCM card 1 'mems-mic' device 0 subdevice 0
[ALSA Debug Hook] hw_params:
Hooks PCM
Slave: Soft volume PCM
Control: Boost Capture Volume
min_dB: -3
max_dB: 50
resolution: 256
Its setup is:
stream : CAPTURE
access : RW_INTERLEAVED
format : S32_LE
subformat : STD
channels : 2
rate : 48000
exact rate : 48000 (48000/1)
msbits : 32
buffer_size : 65536
period_size : 16384
period_time : 341333
tstamp_mode : NONE
period_step : 1
avail_min : 16384
period_event : 0
start_threshold : 1
stop_threshold : 65536
silence_threshold: 0
silence_size : 0
boundary : 1073741824
Slave: Route conversion PCM
Transformation table:
0 <- 0
1 <- 0
Its setup is:
stream : CAPTURE
access : MMAP_INTERLEAVED
format : S32_LE
subformat : STD
channels : 2
rate : 48000
exact rate : 48000 (48000/1)
msbits : 32
buffer_size : 65536
period_size : 16384
period_time : 341333
tstamp_mode : NONE
period_step : 1
avail_min : 16384
period_event : 0
start_threshold : 1
stop_threshold : 65536
silence_threshold: 0
silence_size : 0
boundary : 1073741824
Slave: Mmap emulation PCM
Its setup is:
stream : CAPTURE
access : MMAP_INTERLEAVED
format : S32_LE
subformat : STD
channels : 2
rate : 48000
exact rate : 48000 (48000/1)
msbits : 32
buffer_size : 65536
period_size : 16384
period_time : 341333
tstamp_mode : NONE
period_step : 1
avail_min : 16384
period_event : 0
start_threshold : 1
stop_threshold : 65536
silence_threshold: 0
silence_size : 0
boundary : 1073741824
Slave: Hardware PCM card 1 'mems-mic' device 0 subdevice 0
Its setup is:
stream : CAPTURE
access : RW_INTERLEAVED
format : S32_LE
subformat : STD
channels : 2
rate : 48000
exact rate : 48000 (48000/1)
msbits : 32
buffer_size : 65536
period_size : 16384
period_time : 341333
tstamp_mode : NONE
period_step : 1
avail_min : 16384
period_event : 0
start_threshold : 1073741824
stop_threshold : 65536
silence_threshold: 0
silence_size : 0
boundary : 1073741824
appl_ptr : 0
hw_ptr : 0
[alsa @ 0x31ea450] All info found
[alsa @ 0x31ea450] stream 0: start_time: 1487382765.290 duration:
-9223372036854.775
[alsa @ 0x31ea450] format: start_time: 1487382765.290 duration:
-9223372036854.775 bitrate=3072 kb/s
Guessed Channel Layout for Input Stream #0.0 : stereo
Input #0, alsa, from 'michooks':
Duration: N/A, start: 1487382765.289814, bitrate: 3072 kb/s
Stream #0:0, 1, 1/1000000: Audio: pcm_s32le, 48000 Hz, stereo, s32,
3072 kb/s
Successfully opened the file.
Parsing a group of options: output url -.
Applying option f (force format) with argument null.
Successfully parsed a group of options.
Opening an output file: -.
Successfully opened the file.
detected 1 logical cores
[graph_0_in_0_0 @ 0x31f9310] Setting 'time_base' to value '1/48000'
[graph_0_in_0_0 @ 0x31f9310] Setting 'sample_rate' to value '48000'
[graph_0_in_0_0 @ 0x31f9310] Setting 'sample_fmt' to value 's32'
[graph_0_in_0_0 @ 0x31f9310] Setting 'channel_layout' to value '0x3'
[graph_0_in_0_0 @ 0x31f9310] tb:1/48000 samplefmt:s32 samplerate:48000
chlayout:0x3
[format_out_0_0 @ 0x31f9f10] Setting 'sample_fmts' to value 's16'
[format_out_0_0 @ 0x31f9f10] auto-inserting filter 'auto_resampler_0'
between the filter 'Parsed_anull_0' and the filter 'format_out_0_0'
[AVFilterGraph @ 0x31f9980] query_formats: 4 queried, 6 merged, 3 already
done, 0 delayed
[auto_resampler_0 @ 0x31faf10] [SWR @ 0x321e130] Using fltp internally
between filters
[auto_resampler_0 @ 0x31faf10] ch:2 chl:stereo fmt:s32 r:48000Hz -> ch:2
chl:stereo fmt:s16 r:48000Hz
Output #0, null, to 'pipe:':
Metadata:
encoder : Lavf57.66.101
Stream #0:0, 0, 1/48000: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536
kb/s
Metadata:
encoder : Lavc57.75.100 pcm_s16le
Stream mapping:
Stream #0:0 -> #0:0 (pcm_s32le (native) -> pcm_s16le (native))
Press [q] to stop, [?] for help
cur_dts is invalid (this is harmless if it occurs once at the start per
stream)
size=N/A time=00:00:17.84 bitrate=N/A speed= 1x
video:0kB audio:3345kB subtitle:0kB other streams:0kB global headers:0kB
muxing overhead: unknown
Input file #0 (michooks):
Input stream #0:0 (audio): 26372 packets read (6851424 bytes); 26372
frames decoded (856428 samples);
Total: 26372 packets (6851424 bytes) demuxed
Output file #0 (pipe:):
Output stream #0:0 (audio): 26372 frames encoded (856428 samples); 26372
packets muxed (3425712 bytes);
Total: 26372 packets (3425712 bytes) muxed
26372 frames successfully decoded, 0 decoding errors
Exiting normally, received signal 2.
Here is the console output of Arecord:
$ arecord -v -r48000 -c2 -fS32_LE --period-size=16384 --buffer-size=65536
-Dmic_sv -twav /dev/null
Recording WAVE '/dev/null' : Signed 32 bit Little Endian, Rate 48000 Hz,
Stereo
Soft volume PCM
Control: Boost Capture Volume
min_dB: -3
max_dB: 50
resolution: 256
Its setup is:
stream : CAPTURE
access : RW_INTERLEAVED
format : S32_LE
subformat : STD
channels : 2
rate : 48000
exact rate : 48000 (48000/1)
msbits : 32
buffer_size : 65536
period_size : 16384
period_time : 341333
tstamp_mode : NONE
period_step : 1
avail_min : 16384
period_event : 0
start_threshold : 1
stop_threshold : 65536
silence_threshold: 0
silence_size : 0
boundary : 1073741824
Slave: Route conversion PCM
Transformation table:
0 <- 0
1 <- 0
Its setup is:
stream : CAPTURE
access : MMAP_INTERLEAVED
format : S32_LE
subformat : STD
channels : 2
rate : 48000
exact rate : 48000 (48000/1)
msbits : 32
buffer_size : 65536
period_size : 16384
period_time : 341333
tstamp_mode : NONE
period_step : 1
avail_min : 16384
period_event : 0
start_threshold : 1
stop_threshold : 65536
silence_threshold: 0
silence_size : 0
boundary : 1073741824
Slave: Mmap emulation PCM
Its setup is:
stream : CAPTURE
access : MMAP_INTERLEAVED
format : S32_LE
subformat : STD
channels : 2
rate : 48000
exact rate : 48000 (48000/1)
msbits : 32
buffer_size : 65536
period_size : 16384
period_time : 341333
tstamp_mode : NONE
period_step : 1
avail_min : 16384
period_event : 0
start_threshold : 1
stop_threshold : 65536
silence_threshold: 0
silence_size : 0
boundary : 1073741824
Slave: Hardware PCM card 1 'mems-mic' device 0 subdevice 0
Its setup is:
stream : CAPTURE
access : RW_INTERLEAVED
format : S32_LE
subformat : STD
channels : 2
rate : 48000
exact rate : 48000 (48000/1)
msbits : 32
buffer_size : 65536
period_size : 16384
period_time : 341333
tstamp_mode : NONE
period_step : 1
avail_min : 16384
period_event : 0
start_threshold : 1073741824
stop_threshold : 65536
silence_threshold: 0
silence_size : 0
boundary : 1073741824
appl_ptr : 0
hw_ptr : 0
^CAborted by signal Interrupt...
On Fri, Feb 17, 2017 at 5:38 PM, christina zou <zou.christ...@gmail.com>
wrote:
> Hi Carl (and all),
>
> Well, I can't remove the -acodec pcm_s32le option. If I just run:
>
> ffmpeg -f alsa -i mic_sv temp.wav
>
> '[alsa @ 0x243b3f0] cannot set sample format 0x10000 2 (Invalid argument)
> mic_sv: Input/output error'
>
> > Next step will be to copy the options used for arecord.
> I already made sure the arecord and ffmpeg PCM options are identical. I
> have just written a custom ALSA hook ('michooks') in ffmpeg that dumps all
> the PCM settings. Here is the result:
>
> 1. arecord -v -r48000 -c2 -fS32_LE --period-size=16384 --buffer-size=65536
> -Dmic_sv -twav /dev/null
>
> Uses 5% CPU. Console output: http://vpaste.net/CPk3A
>
> 2. ALSA_CONFIG_PATH=/usr/share/alsa/alsa.conf:./dumpasoundrc ffmpeg -f alsa
> -acodec pcm_s32le -i michooks -f null -
>
> Uses 95% CPU. Console output: http://vpaste.net/xSvae
>
> You can see that I've configured arecord/FFMPEG to have identical settings
> (buffer sizes, period sizes, etc.)
>
>
> Any thoughts? Thank you,
>
> Christina
>
> On Fri, Feb 17, 2017 at 3:43 AM, Carl Eugen Hoyos <ceffm...@gmail.com>
> wrote:
>
>> 2017-02-17 12:19 GMT+01:00 christina zou <zou.christ...@gmail.com>:
>> > Hi Carl,
>> >
>> > Thanks for the quick reply!!
>> >
>> > My mic natively records in 32bit LE format. I thought -acodec
>> > pcm_s32le was merely supplying the input format?
>>
>> You are right and it seems to work here but since you are reporting an
>> issue I would suggest to try with default values first.
>>
>> Carl Eugen
>> _______________________________________________
>> 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".
>>
>
>
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