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  • D3D11 hardware screen recording with ffmpeg using Intel H264 QSV hardware encoding

    13 mai 2024, par Cactus

    I'm trying to screen record using ffmpeg and having it all done via hardware on my Intel integrated graphics.

    


    Specs

    


    For reference, here are my specs :

    


      

    • Windows 11 Pro Version 10.0.22631 Build 22631
    • 


    • Model : Dell Inc. OptiPlex 3090
    • 


    • Processor : 11th Gen Intel(R) Core(TM) i3-1115G4 @ 3.00GHz, 2995 Mhz, 2 Core(s), 4 Logical Processor(s)
    • 


    • Terminal : Windows Terminal using Windows Powershell
    • 


    


    In this wiki, it looked like I could use the "Windows 8+ Desktop Duplication API" to be "directly encoded by a compatible hardware encoder" — so I thought that I could use h264_qsv to encode, allowing me to record without much performance overhead costs.

    


    Attempt 1

    


    I've tried copying one of the command examples, but it didn't work :

    


    ffmpeg -init_hw_device d3d11va -filter_complex ddagrab=0 


    


    Output :

    


    ffmpeg version 2024-05-02-git-71669f2ad5-full_build-www.gyan.dev Copyright (c) 2000-2024 the FFmpeg developers
  built with gcc 13.2.0 (Rev5, Built by MSYS2 project)
  configuration: --enable-gpl --enable-version3 --enable-static --disable-w32threads --disable-autodetect --enable-fontconfig --enable-iconv --enable-gnutls --enable-libxml2 --enable-gmp --enable-bzlib --enable-lzma --enable-libsnappy --enable-zlib --enable-librist --enable-libsrt --enable-libssh --enable-libzmq --enable-avisynth --enable-libbluray --enable-libcaca --enable-sdl2 --enable-libaribb24 --enable-libaribcaption --enable-libdav1d --enable-libdavs2 --enable-libuavs3d --enable-libxevd --enable-libzvbi --enable-librav1e --enable-libsvtav1 --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs2 --enable-libxeve --enable-libxvid --enable-libaom --enable-libjxl --enable-libopenjpeg --enable-libvpx --enable-mediafoundation --enable-libass --enable-frei0r --enable-libfreetype --enable-libfribidi --enable-libharfbuzz --enable-liblensfun --enable-libvidstab --enable-libvmaf --enable-libzimg --enable-amf --enable-cuda-llvm --enable-cuvid --enable-dxva2 --enable-d3d11va --enable-d3d12va --enable-ffnvcodec --enable-libvpl --enable-nvdec --enable-nvenc --enable-vaapi --enable-libshaderc --enable-vulkan --enable-libplacebo --enable-opencl --enable-libcdio --enable-libgme --enable-libmodplug --enable-libopenmpt --enable-libopencore-amrwb --enable-libmp3lame --enable-libshine --enable-libtheora --enable-libtwolame --enable-libvo-amrwbenc --enable-libcodec2 --enable-libilbc --enable-libgsm --enable-libopencore-amrnb --enable-libopus --enable-libspeex --enable-libvorbis --enable-ladspa --enable-libbs2b --enable-libflite --enable-libmysofa --enable-librubberband --enable-libsoxr --enable-chromaprint
  libavutil      59. 16.101 / 59. 16.101
  libavcodec     61.  5.103 / 61.  5.103
  libavformat    61.  3.103 / 61.  3.103
  libavdevice    61.  2.100 / 61.  2.100
  libavfilter    10.  2.101 / 10.  2.101
  libswscale      8.  2.100 /  8.  2.100
  libswresample   5.  2.100 /  5.  2.100
  libpostproc    58.  2.100 / 58.  2.100
Stream mapping:
  ddagrab:default -> Stream #0:0 (h264_qsv)
Press [q] to stop, [?] for help
Impossible to convert between the formats supported by the filter 'Parsed_ddagrab_0' and the filter 'auto_scale_0'
[fc#0 @ 000001e4ed4393c0] Error configuring filter graph: Function not implemented
[fc#0 @ 000001e4ed4393c0] Task finished with error code: -40 (Function not implemented)
[fc#0 @ 000001e4ed4393c0] Terminating thread with return code -40 (Function not implemented)
[vost#0:0/h264_qsv @ 000001e4ed454000] Could not open encoder before EOF
[vost#0:0/h264_qsv @ 000001e4ed454000] Task finished with error code: -22 (Invalid argument)
[vost#0:0/h264_qsv @ 000001e4ed454000] Terminating thread with return code -22 (Invalid argument)
[out#0/matroska @ 000001e4ed453280] Nothing was written into output file, because at least one of its streams received no packets.
frame=    0 fps=0.0 q=0.0 Lsize=       0KiB time=N/A bitrate=N/A speed=N/A
Conversion failed!


    


    Attempt 2

    


    I then tried copying one of the command examples in the linked ddagrab wiki page, but also no luck.

    


    ffmpeg -f lavfi -i ddagrab -c:v h264_qsv output.mkv


    


    Output :

    


    ffmpeg version 2024-05-02-git-71669f2ad5-full_build-www.gyan.dev Copyright (c) 2000-2024 the FFmpeg developers
  built with gcc 13.2.0 (Rev5, Built by MSYS2 project)
  configuration: --enable-gpl --enable-version3 --enable-static --disable-w32threads --disable-autodetect --enable-fontconfig --enable-iconv --enable-gnutls --enable-libxml2 --enable-gmp --enable-bzlib --enable-lzma --enable-libsnappy --enable-zlib --enable-librist --enable-libsrt --enable-libssh --enable-libzmq --enable-avisynth --enable-libbluray --enable-libcaca --enable-sdl2 --enable-libaribb24 --enable-libaribcaption --enable-libdav1d --enable-libdavs2 --enable-libuavs3d --enable-libxevd --enable-libzvbi --enable-librav1e --enable-libsvtav1 --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs2 --enable-libxeve --enable-libxvid --enable-libaom --enable-libjxl --enable-libopenjpeg --enable-libvpx --enable-mediafoundation --enable-libass --enable-frei0r --enable-libfreetype --enable-libfribidi --enable-libharfbuzz --enable-liblensfun --enable-libvidstab --enable-libvmaf --enable-libzimg --enable-amf --enable-cuda-llvm --enable-cuvid --enable-dxva2 --enable-d3d11va --enable-d3d12va --enable-ffnvcodec --enable-libvpl --enable-nvdec --enable-nvenc --enable-vaapi --enable-libshaderc --enable-vulkan --enable-libplacebo --enable-opencl --enable-libcdio --enable-libgme --enable-libmodplug --enable-libopenmpt --enable-libopencore-amrwb --enable-libmp3lame --enable-libshine --enable-libtheora --enable-libtwolame --enable-libvo-amrwbenc --enable-libcodec2 --enable-libilbc --enable-libgsm --enable-libopencore-amrnb --enable-libopus --enable-libspeex --enable-libvorbis --enable-ladspa --enable-libbs2b --enable-libflite --enable-libmysofa --enable-librubberband --enable-libsoxr --enable-chromaprint
  libavutil      59. 16.101 / 59. 16.101
  libavcodec     61.  5.103 / 61.  5.103
  libavformat    61.  3.103 / 61.  3.103
  libavdevice    61.  2.100 / 61.  2.100
  libavfilter    10.  2.101 / 10.  2.101
  libswscale      8.  2.100 /  8.  2.100
  libswresample   5.  2.100 /  5.  2.100
  libpostproc    58.  2.100 / 58.  2.100
Input #0, lavfi, from 'ddagrab':
  Duration: N/A, start: 0.000000, bitrate: N/A
  Stream #0:0: Video: wrapped_avframe, d3d11, 1920x1080 [SAR 1:1 DAR 16:9], 30 fps, 30 tbr, 1000k tbn
File 'output.mkv' already exists. Overwrite? [y/N] y
Stream mapping:
  Stream #0:0 -> #0:0 (wrapped_avframe (native) -> h264 (h264_qsv))
Press [q] to stop, [?] for help
Impossible to convert between the formats supported by the filter 'Parsed_null_0' and the filter 'auto_scale_0'
[vf#0:0 @ 00000115e105bd40] Error reinitializing filters!
[vf#0:0 @ 00000115e105bd40] Task finished with error code: -40 (Function not implemented)
[vf#0:0 @ 00000115e105bd40] Terminating thread with return code -40 (Function not implemented)
[vost#0:0/h264_qsv @ 00000115e105aa00] Could not open encoder before EOF
[vost#0:0/h264_qsv @ 00000115e105aa00] Task finished with error code: -22 (Invalid argument)
[vost#0:0/h264_qsv @ 00000115e105aa00] Terminating thread with return code -22 (Invalid argument)
[out#0/matroska @ 00000115e1054b80] Nothing was written into output file, because at least one of its streams received no packets.
frame=    0 fps=0.0 q=0.0 Lsize=       0KiB time=N/A bitrate=N/A speed=N/A
Conversion failed!


    


    My main problem is that I don't know how to use really any of these encoders and the examples I've found above don't work with me. What command should I use to screen record all with hardware acceleration on my Intel system ? I don't care about any presets or other options at the moment.

    


    Is there also a way to record audio ? When I tried to use -f dshow -i audio="Stereo Mix (Realtek(R) Audio)" by itself, which I made sure was turned on in Windows' settings and named correctly, it didn't work (is it because I'm using Bluetooth headphones that isn't connected to Realtek's system ?). Should this question be made separately than this one ?

    


  • I have an application in flask where it streams a camera using ffmpeg, the problem is that I can not display the video from the camera using the GPU [closed]

    17 janvier, par Ruben

    I'll put you in context, I am using flask (python) to display a camera in the browser to stream it, for this I use the following Python code :

    


    command = [
     'ffmpeg',
     '-loglevel', 'warning',
     '-rtsp_transport', 'tcp',
     '-i', self.config['url'],
     '-map', '0:v:0', # fuerzo que solo procese el video
     '-vf', f'fps={self.config["fps"]},scale=640:360:force_original_aspect_ratio=decrease',
     '-c:v', 'h264_nvenc', # especificamos que queremos tirar de la gpu de nvidia
     '-preset', 'p7', # ajusta para la maxima calidad/velocidad (p1 mas rapida pero peor calidad - p7 más lento pero mejor calidad)
     '-qp', self.config['quality'], # control de calidad del codificador (0 [mejor calidad] - 51 [peor calidad])
     '-pix_fmt', 'yuv444p', # se mete explicitamente el formato de pixeles
     '-color_range', 'pc',
     '-an', # desactiva el audio
     '-f', 'image2pipe',
     'pipe:1'
] 

self.process = subprocess.Popen(
   command,
   stdout=subprocess.PIPE,
   stderr=subprocess.PIPE,
   bufsize=10**8
)


    


    The problem is that it does not display the video streaming, but it connects correctly to the camera.

    


    On the other hand, It show me the following warnings, which may have something to do with the display, it's probably the second warning that has to do with the pixel format :

    


    DEBUG :main:FFmpeg [camera1] : Guessed Channel Layout for Input Stream #0.1 : mono
DEBUG :main:FFmpeg [camera1] : [swscaler @ 0x560f70b78680] deprecated pixel format used, make sure you did set range correctly

    


    The server has different encodes installed :

    


    DEV.LS h264 H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 (decoders : h264 h264_v4l2m2m h264_qsv h264_cuvid ) (encoders : libx264 libx264rgb h264_nvenc h264_omx h264_qsv h264_v4l2m2m h264_vaapi nvenc nvenc_h264 )

    


    Y uso el h264_nvenc, tambien el servidor tiene soporte de aceleración de hardware con :

    


    libavutil 56. 70.100 / 56. 70.100
libavcodec 58.134.100 / 58.134.100
libavformat 58. 76.100 / 58. 76.100
libavdevice 58. 13.100 / 58. 13.100
libavfilter 7.110.100 / 7.110.100
libswscale 5. 9.100 / 5. 9.100
libswresample 3. 9.100 / 3. 9.100
libpostproc 55. 9.100 / 55. 9.100
Hardware acceleration methods :
vdpau
cuda
vaapi
qsv
drm
opencl

    


    Between them h264_nvenc uses cuda

    


    I expand a little on the information it provides me when using h264_nvenc :

    


    Encoder h264_nvenc [NVIDIA NVENC H.264 encoder]:&#xA;    General capabilities: dr1 delay hardware&#xA;    Threading capabilities: none&#xA;    Supported hardware devices: cuda cuda&#xA;    Supported pixel formats: yuv420p nv12 p010le yuv444p p016le yuv444p16le bgr0 rgb0 cuda&#xA;h264_nvenc AVOptions:&#xA;  -preset            <int>        E..V....... Set the encoding preset (from 0 to 18) (default p4)&#xA;     default         0            E..V.......&#xA;     slow            1            E..V....... hq 2 passes&#xA;     medium          2            E..V....... hq 1 pass&#xA;     fast            3            E..V....... hp 1 pass&#xA;     hp              4            E..V.......&#xA;     hq              5            E..V.......&#xA;     bd              6            E..V.......&#xA;     ll              7            E..V....... low latency&#xA;     llhq            8            E..V....... low latency hq&#xA;     llhp            9            E..V....... low latency hp&#xA;     lossless        10           E..V.......&#xA;     losslesshp      11           E..V.......&#xA;     p1              12           E..V....... fastest (lowest quality)&#xA;     p2              13           E..V....... faster (lower quality)&#xA;     p3              14           E..V....... fast (low quality)&#xA;     p4              15           E..V....... medium (default)&#xA;     p5              16           E..V....... slow (good quality)&#xA;     p6              17           E..V....... slower (better quality)&#xA;     p7              18           E..V....... slowest (best quality)&#xA;  -tune              <int>        E..V....... Set the encoding tuning info (from 1 to 4) (default hq)&#xA;     hq              1            E..V....... High quality&#xA;     ll              2            E..V....... Low latency&#xA;     ull             3            E..V....... Ultra low latency&#xA;     lossless        4            E..V....... Lossless&#xA;  -profile           <int>        E..V....... Set the encoding profile (from 0 to 3) (default main)&#xA;     baseline        0            E..V.......&#xA;     main            1            E..V.......&#xA;     high            2            E..V.......&#xA;     high444p        3            E..V.......&#xA;  -level             <int>        E..V....... Set the encoding level restriction (from 0 to 62) (default auto)&#xA;     auto            0            E..V.......&#xA;     1               10           E..V.......&#xA;     1.0             10           E..V.......&#xA;     1b              9            E..V.......&#xA;     1.0b            9            E..V.......&#xA;     1.1             11           E..V.......&#xA;     1.2             12           E..V.......&#xA;     1.3             13           E..V.......&#xA;     2               20           E..V.......&#xA;     2.0             20           E..V.......&#xA;     2.1             21           E..V.......&#xA;     2.2             22           E..V.......&#xA;     3               30           E..V.......&#xA;     3.0             30           E..V.......&#xA;     3.1             31           E..V.......&#xA;     3.2             32           E..V.......&#xA;     4               40           E..V.......&#xA;     4.0             40           E..V.......&#xA;     4.1             41           E..V.......&#xA;     4.2             42           E..V.......&#xA;     5               50           E..V.......&#xA;     5.0             50           E..V.......&#xA;     5.1             51           E..V.......&#xA;     5.2             52           E..V.......&#xA;     6.0             60           E..V.......&#xA;     6.1             61           E..V.......&#xA;     6.2             62           E..V.......&#xA;  -rc                <int>        E..V....... Override the preset rate-control (from -1 to INT_MAX) (default -1)&#xA;     constqp         0            E..V....... Constant QP mode&#xA;     vbr             1            E..V....... Variable bitrate mode&#xA;     cbr             2            E..V....... Constant bitrate mode&#xA;     vbr_minqp       8388612      E..V....... Variable bitrate mode with MinQP (deprecated)&#xA;     ll_2pass_quality 8388616      E..V....... Multi-pass optimized for image quality (deprecated)&#xA;     ll_2pass_size   8388624      E..V....... Multi-pass optimized for constant frame size (deprecated)&#xA;     vbr_2pass       8388640      E..V....... Multi-pass variable bitrate mode (deprecated)&#xA;     cbr_ld_hq       8388616      E..V....... Constant bitrate low delay high quality mode&#xA;     cbr_hq          8388624      E..V....... Constant bitrate high quality mode&#xA;     vbr_hq          8388640      E..V....... Variable bitrate high quality mode&#xA;  -rc-lookahead      <int>        E..V....... Number of frames to look ahead for rate-control (from 0 to INT_MAX) (default 0)&#xA;  -surfaces          <int>        E..V....... Number of concurrent surfaces (from 0 to 64) (default 0)&#xA;  -cbr               <boolean>    E..V....... Use cbr encoding mode (default false)&#xA;  -2pass             <boolean>    E..V....... Use 2pass encoding mode (default auto)&#xA;  -gpu               <int>        E..V....... Selects which NVENC capable GPU to use. First GPU is 0, second is 1, and so on. (from -2 to INT_MAX) (default any)&#xA;     any             -1           E..V....... Pick the first device available&#xA;     list            -2           E..V....... List the available devices&#xA;  -delay             <int>        E..V....... Delay frame output by the given amount of frames (from 0 to INT_MAX) (default INT_MAX)&#xA;  -no-scenecut       <boolean>    E..V....... When lookahead is enabled, set this to 1 to disable adaptive I-frame insertion at scene cuts (default false)&#xA;  -forced-idr        <boolean>    E..V....... If forcing keyframes, force them as IDR frames. (default false)&#xA;  -b_adapt           <boolean>    E..V....... When lookahead is enabled, set this to 0 to disable adaptive B-frame decision (default true)&#xA;  -spatial-aq        <boolean>    E..V....... set to 1 to enable Spatial AQ (default false)&#xA;  -spatial_aq        <boolean>    E..V....... set to 1 to enable Spatial AQ (default false)&#xA;  -temporal-aq       <boolean>    E..V....... set to 1 to enable Temporal AQ (default false)&#xA;  -temporal_aq       <boolean>    E..V....... set to 1 to enable Temporal AQ (default false)&#xA;  -zerolatency       <boolean>    E..V....... Set 1 to indicate zero latency operation (no reordering delay) (default false)&#xA;  -nonref_p          <boolean>    E..V....... Set this to 1 to enable automatic insertion of non-reference P-frames (default false)&#xA;  -strict_gop        <boolean>    E..V....... Set 1 to minimize GOP-to-GOP rate fluctuations (default false)&#xA;  -aq-strength       <int>        E..V....... When Spatial AQ is enabled, this field is used to specify AQ strength. AQ strength scale is from 1 (low) - 15 (aggressive) (from 1 to 15) (default 8)&#xA;  -cq                <float>      E..V....... Set target quality level (0 to 51, 0 means automatic) for constant quality mode in VBR rate control (from 0 to 51) (default 0)&#xA;  -aud               <boolean>    E..V....... Use access unit delimiters (default false)&#xA;  -bluray-compat     <boolean>    E..V....... Bluray compatibility workarounds (default false)&#xA;  -init_qpP          <int>        E..V....... Initial QP value for P frame (from -1 to 51) (default -1)&#xA;  -init_qpB          <int>        E..V....... Initial QP value for B frame (from -1 to 51) (default -1)&#xA;  -init_qpI          <int>        E..V....... Initial QP value for I frame (from -1 to 51) (default -1)&#xA;  -qp                <int>        E..V....... Constant quantization parameter rate control method (from -1 to 51) (default -1)&#xA;  -weighted_pred     <int>        E..V....... Set 1 to enable weighted prediction (from 0 to 1) (default 0)&#xA;  -coder             <int>        E..V....... Coder type (from -1 to 2) (default default)&#xA;     default         -1           E..V.......&#xA;     auto            0            E..V.......&#xA;     cabac           1            E..V.......&#xA;     cavlc           2            E..V.......&#xA;     ac              1            E..V.......&#xA;     vlc             2            E..V.......&#xA;  -b_ref_mode        <int>        E..V....... Use B frames as references (from 0 to 2) (default disabled)&#xA;     disabled        0            E..V....... B frames will not be used for reference&#xA;     each            1            E..V....... Each B frame will be used for reference&#xA;     middle          2            E..V....... Only (number of B frames)/2 will be used for reference&#xA;  -a53cc             <boolean>    E..V....... Use A53 Closed Captions (if available) (default true)&#xA;  -dpb_size          <int>        E..V....... Specifies the DPB size used for encoding (0 means automatic) (from 0 to INT_MAX) (default 0)&#xA;  -multipass         <int>        E..V....... Set the multipass encoding (from 0 to 2) (default disabled)&#xA;     disabled        0            E..V....... Single Pass&#xA;     qres            1            E..V....... Two Pass encoding is enabled where first Pass is quarter resolution&#xA;     fullres         2            E..V....... Two Pass encoding is enabled where first Pass is full resolution&#xA;  -ldkfs             <int>        E..V....... Low delay key frame scale; Specifies the Scene Change frame size increase allowed in case of single frame VBV and CBR (from 0 to 255) (default 0)&#xA;</int></int></int></boolean></int></int></int></int></int></int></int></boolean></boolean></float></int></boolean></boolean></boolean></boolean></boolean></boolean></boolean></boolean></boolean></boolean></int></int></boolean></boolean></int></int></int></int></int></int></int>

    &#xA;

    If anyone has some idea or needs more information to help me, I would appreciate it.

    &#xA;

  • AAC encoder : Extensive improvements

    11 octobre 2015, par Claudio Freire
    AAC encoder : Extensive improvements
    

    This finalizes merging of the work in the patches in ticket #2686.

    Improvements to twoloop and RC logic are extensive.

    The non-exhaustive list of twoloop improvments includes :
    - Tweaks to distortion limits on the RD optimization phase of twoloop
    - Deeper search in twoloop
    - PNS information marking to let twoloop decide when to use it
    (turned out having the decision made separately wasn’t working)
    - Tonal band detection and priorization
    - Better band energy conservation rules
    - Strict hole avoidance

    For rate control :
    - Use psymodel’s bit allocation to allow proper use of the bit
    reservoir. Don’t work against the bit reservoir by moving lambda
    in the opposite direction when psymodel decides to allocate more/less
    bits to a frame.
    - Retry the encode if the effective rate lies outside a reasonable
    margin of psymodel’s allocation or the selected ABR.
    - Log average lambda at the end. Useful info for everyone, but especially
    for tuning of the various encoder constants that relate to lambda
    feedback.

    Psy :
    - Do not apply lowpass with a FIR filter, instead just let the coder
    zero bands above the cutoff. The FIR filter induces group delay,
    and while zeroing bands causes ripple, it’s lost in the quantization
    noise.
    - Experimental VBR bit allocation code
    - Tweak automatic lowpass filter threshold to maximize audio bandwidth
    at all bitrates while still providing acceptable, stable quality.

    I/S :
    - Phase decision fixes. Unrelated to #2686, but the bugs only surfaced
    when the merge was finalized. Measure I/S band energy accounting for
    phase, and prevent I/S and M/S from being applied both.

    PNS :
    - Avoid marking short bands with PNS when they’re part of a window
    group in which there’s a large variation of energy from one window
    to the next. PNS can’t preserve those and the effect is extremely
    noticeable.

    M/S :
    - Implement BMLD protection similar to the specified in
    ISO-IEC/13818:7-2003, Appendix C Section 6.1. Since M/S decision
    doesn’t conform to section 6.1, a different method had to be
    implemented, but should provide equivalent protection.
    - Move the decision logic closer to the method specified in
    ISO-IEC/13818:7-2003, Appendix C Section 6.1. Specifically,
    make sure M/S needs less bits than dual stereo.
    - Don’t apply M/S in bands that are using I/S

    Now, this of course needed adjustments in the compare targets and
    fuzz factors of the AAC encoder’s fate tests, but if wondering why
    the targets go up (more distortion), consider the previous coder
    was using too many bits on LF content (far more than required by
    psy), and thus those signals will now be more distorted, not less.

    The extra distortion isn’t audible though, I carried extensive
    ABX testing to make sure.

    A very similar patch was also extensively tested by Kamendo2 in
    the context of #2686.

    • [DH] Changelog
    • [DH] libavcodec/aac.h
    • [DH] libavcodec/aaccoder.c
    • [DH] libavcodec/aaccoder_trellis.h
    • [DH] libavcodec/aaccoder_twoloop.h
    • [DH] libavcodec/aacenc.c
    • [DH] libavcodec/aacenc.h
    • [DH] libavcodec/aacenc_is.c
    • [DH] libavcodec/aacenc_is.h
    • [DH] libavcodec/aacenc_pred.c
    • [DH] libavcodec/aacenc_quantization.h
    • [DH] libavcodec/aacenc_utils.h
    • [DH] libavcodec/aacpsy.c
    • [DH] libavcodec/mathops.h
    • [DH] libavcodec/mips/aaccoder_mips.c
    • [DH] libavcodec/psymodel.c
    • [DH] libavcodec/psymodel.h
    • [DH] tests/fate/aac.mak