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• How to increase the compression ratio of a JPEG2000 file with "avenc_jpeg2000" GStreamer encoder ?

  10 juillet 2023, par qfr.bertin.group

  I'm using the plugin avenc_jpeg2000, from gst-libav module, combined with videotestsrc and filesink plugins for encoding a raw picture to a JPEG2000 picture :

  


  gst-launch-1.0 videotestsrc num-buffers=1 ! avenc_jpeg2000 ! filesink location=/tmp/picture-ref.jp2


  


  This pipeline works and produce a 31.85 KiB (32,616) file.

  


  Pipeline graph

  


  Now, I want to divide the size of my output file by two by increasing the compression ratio of the encoder avenc_jpeg2000. To achieve this, I want to minimize the number of bits required to represent the image with an allowable level of distortion. I know JPEG2000 standard support lossless and lossy compression mode. For my use case, the lossy compression mode is acceptable.

  


  How should I proceed to increase the compression of my output file ? What encoder's properties should I play with for doing that ?

  


  My test configuration :

  


  


  • i.MX 8M Plus

    


  


  • GStreamer 1.18.0

    


  


  • libav 1.18.0 (Release date : 2020-09-08)

    


  


  


  I tried to play with "bitrate" and "bitrate-tolerance" properties, but it seems to have no effect on the size of the output file :

  


  gst-launch-1.0 videotestsrc num-buffers=1 ! avenc_jpeg2000 bitrate=100000 bitrate-tolerance=10000 ! filesink location=/tmp/picture-test-01.jp2


  


  I compare files by doing a checksum with sha224sum command :

  


  d0da9118a9c93a0420d6d62f104e0d99fe6e50cda5e87a46cef126f9  /tmp/picture-ref.jp2

d0da9118a9c93a0420d6d62f104e0d99fe6e50cda5e87a46cef126f9  /tmp/picture-test-01.jp2


  


• FFMPEG PNG sequence into mkv cause "inflate returned error -3" every 600-800 frames [closed]

  30 novembre 2023, par sergey9295

  I am new to ffmpeg. I try to use it for creating videos from png sequences. I have uncompressed pngs. All of them rgb24 format.

  


  But during encoding process I get inflate errors. I compared PNG and video frame by frame. And video have approximately 1 dupe frame every 600-800 frames instead of the ones that should be on that places. I tried another codecs, tried to clear png's EXIF(it made things even worse), made sure that memory was enough. Doesn't matter.

  


  The worst part is that this errors are pretty random. I encode one sequence 3 times and get 3 different sets of error-causing frames.

  


  FFMPEG was downloaded from official site.

  


  PS C:\Users\sergey9295\Desktop\Upscaler\bin> ./ffmpeg -framerate 24000/1001 -i 24o/frame%04d.png -c:v libx264 -qp 0 -r 24000/1001 -pix_fmt yuv420p BC108K.mkv
ffmpeg version N-112872-g67ce690bc6-20231128 Copyright (c) 2000-2023 the FFmpeg developers
  built with gcc 13.2.0 (crosstool-NG 1.25.0.232_c175b21)
  configuration: --prefix=/ffbuild/prefix --pkg-config-flags=--static --pkg-config=pkg-config --cross-prefix=x86_64-w64-mingw32- --arch=x86_64 --target-os=mingw32 --enable-gpl --enable-version3 --disable-debug --disable-w32threads --enable-pthreads --enable-iconv --enable-libxml2 --enable-zlib --enable-libfreetype --enable-libfribidi --enable-gmp --enable-lzma --enable-fontconfig --enable-libharfbuzz --enable-libvorbis --enable-opencl --disable-libpulse --enable-libvmaf --disable-libxcb --disable-xlib --enable-amf --enable-libaom --enable-libaribb24 --enable-avisynth --enable-chromaprint --enable-libdav1d --enable-libdavs2 --disable-libfdk-aac --enable-ffnvcodec --enable-cuda-llvm --enable-frei0r --enable-libgme --enable-libkvazaar --enable-libaribcaption --enable-libass --enable-libbluray --enable-libjxl --enable-libmp3lame --enable-libopus --enable-librist --enable-libssh --enable-libtheora --enable-libvpx --enable-libwebp --enable-lv2 --enable-libvpl --enable-openal --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopenmpt --enable-librav1e --enable-librubberband --enable-schannel --enable-sdl2 --enable-libsoxr --enable-libsrt --enable-libsvtav1 --enable-libtwolame --enable-libuavs3d --disable-libdrm --enable-vaapi --enable-libvidstab --enable-vulkan --enable-libshaderc --enable-libplacebo --enable-libx264 --enable-libx265 --enable-libxavs2 --enable-libxvid --enable-libzimg --enable-libzvbi --extra-cflags=-DLIBTWOLAME_STATIC --extra-cxxflags= --extra-ldflags=-pthread --extra-ldexeflags= --extra-libs=-lgomp --extra-version=20231128
  libavutil      58. 32.100 / 58. 32.100
  libavcodec     60. 35.100 / 60. 35.100
  libavformat    60. 18.100 / 60. 18.100
  libavdevice    60.  4.100 / 60.  4.100
  libavfilter     9. 13.100 /  9. 13.100
  libswscale      7.  6.100 /  7.  6.100
  libswresample   4. 13.100 /  4. 13.100
  libpostproc    57.  4.100 / 57.  4.100
Input #0, image2, from '24o/frame%04d.png':
  Duration: 00:01:32.09, start: 0.000000, bitrate: N/A
  Stream #0:0: Video: png, rgb24(pc, gbr/bt709/iec61966-2-1), 7680x4320, 23.98 fps, 23.98 tbr, 23.98 tbn
Stream mapping:
  Stream #0:0 -> #0:0 (png (native) -> h264 (libx264))
Press [q] to stop, [?] for help
[libx264 @ 00000231363c6280] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2
[libx264 @ 00000231363c6280] profile High 4:4:4 Predictive, level 6.0, 4:2:0, 8-bit
[libx264 @ 00000231363c6280] 64 - core 164 - H.264/MPEG-4 AVC codec - Copyleft 2003-2023 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=0 mixed_ref=1 me_range=16 chroma_me=1 trellis=0 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=0 chroma_qp_offset=0 threads=18 lookahead_threads=3 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=2 keyint=250 keyint_min=23 scenecut=40 intra_refresh=0 rc=cqp mbtree=0 qp=0
Output #0, matroska, to 'BC108K.mkv':
  Metadata:
    encoder         : Lavf60.18.100
  Stream #0:0: Video: h264 (H264 / 0x34363248), yuv420p(tv, unknown/bt709/iec61966-2-1, progressive), 7680x4320, q=2-31, 23.98 fps, 1k tbn
    Metadata:
      encoder         : Lavc60.35.100 libx264
    Side data:
      cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: N/A
[png @ 00000231363c8880] inflate returned error -301:02.72 bitrate=698356.0kbits/s speed=0.171x
[vist#0:0/png @ 00000231363c16c0] Error submitting packet to decoder: Generic error in an external library
[png @ 00000231363c8880] inflate returned error -301:15.24 bitrate=679969.1kbits/s dup=1 drop=0 speed=0.172x
[vist#0:0/png @ 00000231363c16c0] Error submitting packet to decoder: Generic error in an external library3x
[png @ 00000231363f32c0] inflate returned error -301:16.65 bitrate=694583.2kbits/s dup=2 drop=0 speed=0.171x
[vist#0:0/png @ 00000231363c16c0] Error submitting packet to decoder: Generic error in an external library1x
[png @ 000002313646a100] inflate returned error -301:20.78 bitrate=742902.6kbits/s dup=3 drop=0 speed=0.167x
[vist#0:0/png @ 00000231363c16c0] Error submitting packet to decoder: Generic error in an external library6x
[png @ 000002313646ea00] inflate returned error -301:26.92 bitrate=839679.5kbits/s dup=4 drop=0 speed=0.159x
[vist#0:0/png @ 00000231363c16c0] Error submitting packet to decoder: Generic error in an external library8x
[png @ 00000231363cc740] inflate returned error -301:29.38 bitrate=874703.4kbits/s dup=5 drop=0 speed=0.156x
[vist#0:0/png @ 00000231363c16c0] Error submitting packet to decoder: Generic error in an external library6x
[out#0/matroska @ 00000231363a7200] video:9827779kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.000442%
frame= 2208 fps=3.8 q=-1.0 Lsize= 9827822kB time=00:01:32.05 bitrate=874625.3kbits/s dup=6 drop=0 speed=0.158x


  


  IMO the problem is zlib from libpng. But I don't have skills to recompile it with libspng that doesn't require zlib. Maybe there is a ffmpeg version without this error ?

  


• R "only" substitute of the av package to split and convert an mp4 into multiple mp3 [closed]

  9 février 2024, par Bakaburg

  I am developing an R package that requires splitting an mp4 file into multiple segments and converting these segments into mp3 format. Currently, I use the av package for this task. However, av depends on the external ffmpeg tool, necessitating separate installation. This dependency complicates the setup for non-expert users of my package.

  


  I am seeking an alternative approach that either uses only R or incorporates a low-level solution directly within the package, eliminating the need for external tool installations. The goal is to streamline the user experience by minimizing setup complexity.

  


  Does anyone know of such a solution or approach that can substitute the functionality provided by av without external dependencies ?