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Getting ffmpeg output with QProccess

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  • S Offline
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    SGaist
    Lifetime Qt Champion
    wrote on 26 Apr 2020, 13:28 last edited by
    #6

    QProcess::readStandardError
    QProcess:exitCode
    QProcess::exitStatus

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    R 1 Reply Last reply 26 Apr 2020, 13:33
    1
    • S SGaist
      26 Apr 2020, 13:28

      QProcess::readStandardError
      QProcess:exitCode
      QProcess::exitStatus

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      rktech
      wrote on 26 Apr 2020, 13:33 last edited by
      #7

      @SGaist How to correctly use readStandartError? Print in qDebug?

      R S 2 Replies Last reply 26 Apr 2020, 13:36
      0
      • R rktech
        26 Apr 2020, 13:33

        @SGaist How to correctly use readStandartError? Print in qDebug?

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        rktech
        wrote on 26 Apr 2020, 13:36 last edited by
        #8

        @rktech exitStatus: QProcess::NormalExit, exitCode: 1

        R 1 Reply Last reply 26 Apr 2020, 13:41
        0
        • R rktech
          26 Apr 2020, 13:33

          @SGaist How to correctly use readStandartError? Print in qDebug?

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          SGaist
          Lifetime Qt Champion
          wrote on 26 Apr 2020, 13:41 last edited by
          #9

          @rktech said in Getting ffmpeg output with QProccess:

          @SGaist How to correctly use readStandartError? Print in qDebug?

          That's one way yes.

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          • R rktech
            26 Apr 2020, 13:36

            @rktech exitStatus: QProcess::NormalExit, exitCode: 1

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            rktech
            wrote on 26 Apr 2020, 13:41 last edited by
            #10

            @rktech readStandartError
            ffmpeg version git-2020-04-24-a501947 Copyright (c) 2000-2020 the FFmpeg developers\r\n built with gcc 9.3.1 (GCC) 20200328\r\n configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libsrt --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --disable-w32threads --enable-libmfx --enable-ffnvcodec --enable-cuda-llvm --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt --enable-amf\r\n libavutil 56. 42.102 / 56. 42.102\r\n libavcodec 58. 81.100 / 58. 81.100\r\n libavformat 58. 42.101 / 58. 42.101\r\n libavdevice 58. 9.103 / 58. 9.103\r\n libavfilter 7. 79.100 / 7. 79.100\r\n libswscale 5. 6.101 / 5. 6.101\r\n libswresample 3. 6.100 / 3. 6.100\r\n libpostproc 55. 6.100 / 55. 6.100\r\n[NULL @ 0000024fd452b800] Unable to find a suitable output format for ' -i'\r\n -i: Invalid argument\r\n

            I would drop error, but same as in my first post.

            R 1 Reply Last reply 26 Apr 2020, 13:42
            0
            • R rktech
              26 Apr 2020, 13:41

              @rktech readStandartError
              ffmpeg version git-2020-04-24-a501947 Copyright (c) 2000-2020 the FFmpeg developers\r\n built with gcc 9.3.1 (GCC) 20200328\r\n configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libsrt --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --disable-w32threads --enable-libmfx --enable-ffnvcodec --enable-cuda-llvm --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt --enable-amf\r\n libavutil 56. 42.102 / 56. 42.102\r\n libavcodec 58. 81.100 / 58. 81.100\r\n libavformat 58. 42.101 / 58. 42.101\r\n libavdevice 58. 9.103 / 58. 9.103\r\n libavfilter 7. 79.100 / 7. 79.100\r\n libswscale 5. 6.101 / 5. 6.101\r\n libswresample 3. 6.100 / 3. 6.100\r\n libpostproc 55. 6.100 / 55. 6.100\r\n[NULL @ 0000024fd452b800] Unable to find a suitable output format for ' -i'\r\n -i: Invalid argument\r\n

              I would drop error, but same as in my first post.

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              rktech
              wrote on 26 Apr 2020, 13:42 last edited by
              #11

              @rktech That was caused by splitting parametrs into list, but the problem with wrong error continues:
              "ffmpeg version git-2020-04-24-a501947 Copyright (c) 2000-2020 the FFmpeg developers\r\n built with gcc 9.3.1 (GCC) 20200328\r\n configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libsrt --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --disable-w32threads --enable-libmfx --enable-ffnvcodec --enable-cuda-llvm --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt --enable-amf\r\n libavutil 56. 42.102 / 56. 42.102\r\n libavcodec 58. 81.100 / 58. 81.100\r\n libavformat 58. 42.101 / 58. 42.101\r\n libavdevice 58. 9.103 / 58. 9.103\r\n libavfilter 7. 79.100 / 7. 79.100\r\n libswscale 5. 6.101 / 5. 6.101\r\n libswresample 3. 6.100 / 3. 6.100\r\n libpostproc 55. 6.100 / 55. 6.100\r\nOutput #0, mp4, to ' -i S01E01.mp4':\r\nOutput file #0 does not contain any stream\r\n"

              1 Reply Last reply
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                SGaist
                Lifetime Qt Champion
                wrote on 26 Apr 2020, 13:47 last edited by
                #12

                Try removing the spaces in the parameter list.

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                • R Offline
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                  rktech
                  wrote on 26 Apr 2020, 13:50 last edited by
                  #13

                  Done like this:

                  params << "-i S01E01.mp4 2>&1";
                  

                  Getting this error:
                  "ffmpeg version git-2020-04-24-a501947 Copyright (c) 2000-2020 the FFmpeg developers\r\n built with gcc 9.3.1 (GCC) 20200328\r\n configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libsrt --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --disable-w32threads --enable-libmfx --enable-ffnvcodec --enable-cuda-llvm --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt --enable-amf\r\n libavutil 56. 42.102 / 56. 42.102\r\n libavcodec 58. 81.100 / 58. 81.100\r\n libavformat 58. 42.101 / 58. 42.101\r\n libavdevice 58. 9.103 / 58. 9.103\r\n libavfilter 7. 79.100 / 7. 79.100\r\n libswscale 5. 6.101 / 5. 6.101\r\n libswresample 3. 6.100 / 3. 6.100\r\n libpostproc 55. 6.100 / 55. 6.100\r\nUnrecognized option 'i S01E01.mp4 2>&1'.\r\nError splitting the argument list: Option not found\r\n"

                  S 1 Reply Last reply 26 Apr 2020, 13:56
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                  • R Offline
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                    rktech
                    wrote on 26 Apr 2020, 13:53 last edited by
                    #14

                    The

                    2>&1
                    

                    Is not the problem, it drops same error without it.

                    1 Reply Last reply
                    0
                    • R rktech
                      26 Apr 2020, 13:50

                      Done like this:

                      params << "-i S01E01.mp4 2>&1";
                      

                      Getting this error:
                      "ffmpeg version git-2020-04-24-a501947 Copyright (c) 2000-2020 the FFmpeg developers\r\n built with gcc 9.3.1 (GCC) 20200328\r\n configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libsrt --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --disable-w32threads --enable-libmfx --enable-ffnvcodec --enable-cuda-llvm --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt --enable-amf\r\n libavutil 56. 42.102 / 56. 42.102\r\n libavcodec 58. 81.100 / 58. 81.100\r\n libavformat 58. 42.101 / 58. 42.101\r\n libavdevice 58. 9.103 / 58. 9.103\r\n libavfilter 7. 79.100 / 7. 79.100\r\n libswscale 5. 6.101 / 5. 6.101\r\n libswresample 3. 6.100 / 3. 6.100\r\n libpostproc 55. 6.100 / 55. 6.100\r\nUnrecognized option 'i S01E01.mp4 2>&1'.\r\nError splitting the argument list: Option not found\r\n"

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                      SGaist
                      Lifetime Qt Champion
                      wrote on 26 Apr 2020, 13:56 last edited by
                      #15

                      params << "-i" << "S01E01.mp4"

                      In any case, "2>&1" is command prompt specific, so it does not make sense to put it there and might even interfere.

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                      Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                      R 1 Reply Last reply 26 Apr 2020, 13:58
                      1
                      • S SGaist
                        26 Apr 2020, 13:56

                        params << "-i" << "S01E01.mp4"

                        In any case, "2>&1" is command prompt specific, so it does not make sense to put it there and might even interfere.

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                        rktech
                        wrote on 26 Apr 2020, 13:58 last edited by
                        #16

                        @SGaist Thanks, now it works

                        1 Reply Last reply
                        0

                        15/16

                        26 Apr 2020, 13:56

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