[FFmpeg-devel] [PATCH 5/5] Add AudioToolbox audio input device.

[Andreas Rheinhardt]

Romain Beauxis:
> Le mer. 19 janv. 2022 à 10:59, Marvin Scholz <epirat07 at gmail.com> a écrit :
>>
>>
>>
>> On 19 Jan 2022, at 15:42, Romain Beauxis wrote:
>>
>> Hi, thanks for the patch. I've not done a full code review yet, just a
>> few
>> initial remarks below:
>>
>>> This patch adds support for a new, audio-specific input device using
>>> the documented and battle-tested AUHAL input. This provides a pendant
>>> to the AudioToolbox audio-only output.
>>>
>>> A couple of advantages for this:
>>> * It avoids a lot of the complexity of supporting audio and video in a
>>> single input
>>> * The AUHAL API seems tested, documented and robust
>>> * This implementation hopefully gives good control over audio latency
>>> and also minimizes data copy
>>> From: Romain Beauxis <toots at rastageeks.org>
>>> To: ffmpeg-devel at ffmpeg.org
>>> Subject: [PATCH] Add AudioToolbox audio input device.
>>> Date: 18. January 2022 at 23:29
>>> Signed-off-by: Romain Beauxis <toots at rastageeks.org>
>>> ---
>>>  configure                      |   5 +
>>>  doc/indevs.texi                |  44 ++++
>>>  libavdevice/Makefile           |   1 +
>>>  libavdevice/alldevices.c       |   1 +
>>>  libavdevice/audiotoolbox_dec.m | 466
>>> +++++++++++++++++++++++++++++++++
>>>  5 files changed, 517 insertions(+)
>>>  create mode 100644 libavdevice/audiotoolbox_dec.m
>>>
>>> diff --git a/configure b/configure
>>> index 1413122d87..80e39aae44 100755
>>> --- a/configure
>>> +++ b/configure
>>> @@ -204,6 +204,7 @@ External library support:
>>>    --disable-avfoundation   disable Apple AVFoundation framework
>>> [autodetect]
>>>    --enable-avisynth        enable reading of AviSynth script files
>>> [no]
>>>    --disable-bzlib          disable bzlib [autodetect]
>>> +  --disable-coremedia      disable Apple CoreMedia framework
>>> [autodetect]
>>>    --disable-coreimage      disable Apple CoreImage framework
>>> [autodetect]
>>>    --enable-chromaprint     enable audio fingerprinting with
>>> chromaprint [no]
>>>    --enable-frei0r          enable frei0r video filtering [no]
>>> @@ -1750,6 +1751,7 @@ EXTERNAL_AUTODETECT_LIBRARY_LIST="
>>>      appkit
>>>      avfoundation
>>>      bzlib
>>> +    coremedia
>>>      coreimage
>>>      iconv
>>>      libxcb
>>> @@ -3493,6 +3495,8 @@ alsa_outdev_deps="alsa"
>>>  avfoundation_indev_deps="avfoundation corevideo coremedia pthreads"
>>>  avfoundation_indev_suggest="coregraphics applicationservices"
>>>  avfoundation_indev_extralibs="-framework Foundation"
>>> +audiotoolbox_indev_deps="coremedia audiotoolbox"
>>> +audiotoolbox_indev_extralibs="-framework CoreMedia -framework
>>> AudioToolbox"
>>>  audiotoolbox_outdev_deps="audiotoolbox pthreads"
>>>  audiotoolbox_outdev_extralibs="-framework AudioToolbox -framework
>>> CoreAudio"
>>>  bktr_indev_deps_any="dev_bktr_ioctl_bt848_h machine_ioctl_bt848_h
>>> dev_video_bktr_ioctl_bt848_h dev_ic_bt8xx_h"
>>> @@ -6340,6 +6344,7 @@ check_lib camera2ndk "stdbool.h stdint.h
>>> camera/NdkCameraManager.h" ACameraManag
>>>  enabled appkit       && check_apple_framework AppKit
>>>  enabled audiotoolbox && check_apple_framework AudioToolbox
>>>  enabled avfoundation && check_apple_framework AVFoundation
>>> +enabled coremedia    && check_apple_framework CoreMedia
>>>  enabled coreimage    && check_apple_framework CoreImage
>>>  enabled metal        && check_apple_framework Metal
>>>  enabled videotoolbox && check_apple_framework VideoToolbox
>>> diff --git a/doc/indevs.texi b/doc/indevs.texi
>>> index 858c0fa4e4..30a91d304f 100644
>>> --- a/doc/indevs.texi
>>> +++ b/doc/indevs.texi
>>> @@ -103,6 +103,50 @@ Set the maximum number of frames to buffer.
>>> Default is 5.
>>>
>>>  @end table
>>>
>>> + at section AudioToolbox
>>> +
>>> +AudioToolbox input device.
>>> +
>>> +Allows native input from CoreAudio devices on OSX.
>> Nit: Nowadays it's macOS instead of OSX
>>
>>> +
>>> +All available devices can be enumerated by using
>>> @option{-list_devices true}, listing
>>> +all device names, and corresponding unique ID.
>>
>> Instead of adding another device that uses a custom list-devices option,
>> could you
>> instead implement the .get_device_list callback? (See alsa or pulse
>> modules for an
>> example) Then listing would work properly with the `ffmpeg -sources`
>> command and
>> devices could be iterated over using the avdevice APIs as well.
>>
>> (Ideally we would have that for AVFoundation too but its really hard now
>> to do that
>> in a backwards compatible manner)
> 
> Is there a way to access the result of the get_devices_callback from
> the ffmpeg CLI? I have searched but haven't found any so far..
> 

-sources or -sinks; you can also add a specific device like "-sources alsa".

- Andreas