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• syntax error on accessing a structure variables

  23 octobre 2013, par JAYANTHI

  This is my code

  typedef struct AVInputFormat {
  
  /**
  
   * A comma separated list of short names for the format. New names
  
   * may be appended with a minor bump.
  
   */
  
  const char *name;
  
  
  
  /**
  
   * Descriptive name for the format, meant to be more human-readable
  
   * than name. You should use the NULL_IF_CONFIG_SMALL() macro
  
   * to define it.
  
   */
  
  const char *long_name;
  
  
  
  /**
  
   * Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS,
  
   * AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH,
  
   * AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK, AVFMT_SEEK_TO_PTS.
  
   */
  
  int flags;
  
  
  
  /**
  
   * If extensions are defined, then no probe is done. You should
  
   * usually not use extension format guessing because it is not
  
   * reliable enough
  
   */
  
  const char *extensions;
  
  
  
  const struct AVCodecTag * const *codec_tag;
  
  
  
  const AVClass *priv_class; ///< AVClass for the private context
  
  
  
  /*****************************************************************
  
   * No fields below this line are part of the public API. They
  
   * may not be used outside of libavformat and can be changed and
  
   * removed at will.
  
   * New public fields should be added right above.
  
   *****************************************************************
  
   */
  
  struct AVInputFormat *next;
  
  
  
  /**
  
   * Raw demuxers store their codec ID here.
  
   */
  
  int raw_codec_id;
  
  
  
  /**
  
   * Size of private data so that it can be allocated in the wrapper.
  
   */
  
  int priv_data_size;
  
  
  
  /**
  
   * Tell if a given file has a chance of being parsed as this format.
  
   * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
  
   * big so you do not have to check for that unless you need more.
  
   */
  
  int (*read_probe)(AVProbeData *);
  
  
  
  /**
  
   * Read the format header and initialize the AVFormatContext
  
   * structure. Return 0 if OK. Only used in raw format right
  
   * now. 'avformat_new_stream' should be called to create new streams.
  
   */
  
  int (*read_header)(struct AVFormatContext *);
  
  
  
  /**
  
   * Read one packet and put it in 'pkt'. pts and flags are also
  
   * set. 'avformat_new_stream' can be called only if the flag
  
   * AVFMTCTX_NOHEADER is used and only in the calling thread (not in a
  
   * background thread).
  
   * @return 0 on success, < 0 on error.
  
   *         When returning an error, pkt must not have been allocated
  
   *         or must be freed before returning
  
   */
  
  int (*read_packet)(struct AVFormatContext *, AVPacket *pkt);
  
  
  
  /**
  
   * Close the stream. The AVFormatContext and AVStreams are not
  
   * freed by this function
  
   */
  
  int (*read_close)(struct AVFormatContext *);
  
  
  
  /**
  
   * Seek to a given timestamp relative to the frames in
  
   * stream component stream_index.
  
   * @param stream_index Must not be -1.
  
   * @param flags Selects which direction should be preferred if no exact
  
   *              match is available.
  
   * @return >= 0 on success (but not necessarily the new offset)
  
   */
  
  int (*read_seek)(struct AVFormatContext *,
  
                   int stream_index, int64_t timestamp, int flags);
  
  
  
  /**
  
   * Get the next timestamp in stream[stream_index].time_base units.
  
   * @return the timestamp or AV_NOPTS_VALUE if an error occurred
  
   */
  
  int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
  
                            int64_t *pos, int64_t pos_limit);
  
  
  
  /**
  
   * Start/resume playing - only meaningful if using a network-based format
  
   * (RTSP).
  
   */
  
  int (*read_play)(struct AVFormatContext *);
  
  
  
  /**
  
   * Pause playing - only meaningful if using a network-based format
  
   * (RTSP).
  
   */
  
  int (*read_pause)(struct AVFormatContext *);
  
  
  
  /**
  
   * Seek to timestamp ts.
  
   * Seeking will be done so that the point from which all active streams
  
   * can be presented successfully will be closest to ts and within min/max_ts.
  
   * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
  
   */
  
  int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
  
  } AVInputFormat;
  
  
  
  AVInputFormat ff_yop_demuxer = {
  
  .name           = "yop",                                               //error here
  
  .long_name      = NULL_IF_CONFIG_SMALL("Psygnosis YOP"),
  
  .priv_data_size = sizeof(YopDecContext),
  
  .read_probe     = yop_probe,
  
  .read_header    = yop_read_header,
  
  .read_packet    = yop_read_packet,
  
  .read_close     = yop_read_close,
  
  .read_seek      = yop_read_seek,
  
  .extensions     = "yop",
  
  .flags          = AVFMT_GENERIC_INDEX,
  
  };

  Getting error like,

  3>c:\users\awki6\desktop\ffmpeg\libavformat\yop.cpp(235): error C2143: syntax error : missing '}' before '.'
3>c:\users\awki6\desktop\ffmpeg\libavformat\yop.cpp(235): error C2143: syntax error : missing ';' before '.'
3>c:\users\awki6\desktop\ffmpeg\libavformat\yop.cpp(235): error C2059: syntax error : '.'
3>c:\users\awki6\desktop\ffmpeg\libavformat\yop.cpp(245): error C2143: syntax error : missing ';' before '}'
3>c:\users\awki6\desktop\ffmpeg\libavformat\yop.cpp(245): error C2059: syntax error : '}'

  Please help me to solve those errors

• AVI compression with ffmpeg while maintaining alpha channel, to use in Adobe Premiere

  12 décembre 2020, par Dsrts

  I am a novice when it comes to handling video conversion/encoding in general, but have spent a few days trying to figure out if ffmpeg, or any other method out there, is able to compress an .avi that has rgb+a. I have been able to get a few files that appear to work when played in VLC, but they wont load into Adobe Premiere to verify that alpha was maintained, and I assume it is a codec issue and/or a pixel format issue, but so far I haven't been able to pinpoint it.

  


  Also, I'm not sure if it's advisable to compress an .avi at all with alpha since it could lead to quality issues from compression. Some loss of quality is ok if it means reducing file size.

  


  My goal is to convert an avi file to a smaller video file, that isn't multiple GB in size. Currently I have 8 sec transparent lower thirds file that is about 2GB in size. Simply adjusting bitrate has not done it, as that seems to wipe out the alpha channel and I end up with RGB with a white background. I have tried using a PNG codec, with various different pixel formats. This yielded files that would open in VLC, but not Adobe Premiere. I suspect that this has something to do with the codec, though as to what it is, I have no idea.

  


  Right now, this seems like it may just not be possible. Here are some examples of what I have tried :

  


  ffmpeg -i "input.avi" -map 0 -c:v png -c:a copy "Compressed.avi"

  


  —this just creates a file that opens in vlc, but not premiere

  


  ffmpeg.exe -i "input.avi" -vcodec png -b:v 64k -pix_fmt rgb32 "Compressed.avi"

  


  —this does the same thing as above, I tried every pixel format on this list with no success.

  


  ffmpeg.exe -i "input.avi" -b:v 64k -pix_fmt bgr32 "Compressed.avi"

  


  —this just results in an avi with a white background, kills alpha.

  


  That is the closest I have come. The bitrate value is likely arbitrary, as I have also tried with and without bitrate modification. I don't know if there is a way to get Premiere to recognize the files that did open in VLC with the PNG codec, or if there is something I am missing, OR if this is just entirely impossible. The output doesn't need to be .avi either, so long as it will open in Premiere.

  


  —
Edit : Requested in the comments, output from ffmpeg -i input.avi

  


  ffmpeg version 4.3.1-2020-11-19-essentials_build-www.gyan.dev Copyright (c) 2000-2020 the FFmpeg developers
  built with gcc 10.2.0 (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-lzma --enable-zlib --enable-libsrt --enable-libssh --enable-libzmq --enable-avisynth --enable-sdl2 --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxvid --enable-libaom --enable-libopenjpeg --enable-libvpx --enable-libass --enable-libfreetype --enable-libfribidi --enable-libvidstab --enable-libvmaf --enable-libzimg --enable-amf --enable-cuda-llvm --enable-cuvid --enable-ffnvcodec --enable-nvdec --enable-nvenc --enable-d3d11va --enable-dxva2 --enable-libmfx --enable-libgme --enable-libopenmpt --enable-libopencore-amrwb --enable-libmp3lame --enable-libtheora --enable-libvo-amrwbenc --enable-libgsm --enable-libopencore-amrnb --enable-libopus --enable-libspeex --enable-libvorbis --enable-librubberband
  libavutil      56. 51.100 / 56. 51.100
  libavcodec     58. 91.100 / 58. 91.100
  libavformat    58. 45.100 / 58. 45.100
  libavdevice    58. 10.100 / 58. 10.100
  libavfilter     7. 85.100 /  7. 85.100
  libswscale      5.  7.100 /  5.  7.100
  libswresample   3.  7.100 /  3.  7.100
  libpostproc    55.  7.100 / 55.  7.100
Input #0, avi, from 'input.avi':
  Metadata:
    date            : 2020-12-09T20:27:57.080928
  Duration: 00:00:10.00, start: 0.000000, bitrate: 1990700 kb/s
    Stream #0:0: Video: rawvideo, bgra, 1920x1080, 1997313 kb/s, 30 fps, 30 tbr, 30 tbn, 30 tbc
At least one output file must be specified


  


  — Edit 2 :
Tried this from the comment and it results in a .mov with preserved alpha but it picks up the white pixel values from text drop shadows, resulting in an outer glow effect instead :

  


  ffmpeg -i "input.avi" -map 0 -pix_fmt rgba -c:v png -c:a copy "compressed.mov"

  


  I also tried the following, and I get dropped frames in addition to similar transparency issues in the drop shadow :

  


  ffmpeg -i "input.avi" -map 0 -pix_fmt rgba -c:v qtrle -c:a copy "compressed.mov"

  


• Choose your favourite logo

  28 septembre 2018, par Matomo Core Team — Community

  We’ve been searching for a new logo and we are now down to the final three designs. We want you, the community, to help us choose our logo as we set the scene for a refreshed and vibrant new look for Matomo.

  Please choose your favourite Matomo logo from the three options below. Voting limited to once per person :)

  • Choose your favorite logo*
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