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• Revision 2b8dc065d1 : google style guide include guards Change-Id : I2c252f3ddcc99e96c1f5d3dab8bcb25a2

  30 novembre 2012, par Jim Bankoski

  Changed Paths : Modify /vp9/common/arm/vp9_bilinearfilter_arm.h Modify /vp9/common/arm/vp9_idct_arm.h Modify /vp9/common/arm/vp9_loopfilter_arm.h Modify /vp9/common/arm/vp9_recon_arm.h Modify /vp9/common/arm/vp9_subpixel_arm.h Modify /vp9/common/vp9_alloccommon.h (...)

• Basic "pass-through" use of FFmpegReader/FFmpegWriter in scikit-video

  6 février 2021, par JonathanZ supports MonicaC

  I am starting to use scikit-video and am having trouble writing files. I have reduced the problem to the simplest possible example

  


  vid_file = "6710185719062326259_stamp_25pct.mp4"
output_file = "out_temp3.mp4"
reader = skvideo.io.FFmpegReader(vid_file)
writer = skvideo.io.FFmpegWriter(output_file)
for frame in reader.nextFrame():
        writer.writeFrame(frame)
writer.close()


  


  I'm playing the files in VLC, and the vid_file is valid but the output file, though playable, is mostly big green blocks (though I can discern some details from the original video in it).

  


  My goal, or course, is to do "interesting" manipulations of the frame before I write it out, but I need to get the "no modifications" version working correctly first. I'm also going to be using this on large files, so the vread/vwrite functions that process an entire file at once are not appropriate.

  


  I'm guessing I need to set the appropriate values in the outputdict parameter for the FFmpegWriter, but there are so many that I don't know where to start. I have tried

  


  writer = skvideo.io.FFmpegWriter(output_file, outputdict={'-crf': '0', '-pix_fmt': 'rgb24'})


  


  (-crf 0 to suppress any compression, -pixfmt rgb24 as that's what FFmpegReader says it delivers by default, but these don't work either.

  


  Any ideas on how to make this work ?

  


  Here's the skvideo.io.ffprobe video information for the input file.

  


  {
    "@index": "0",
    "@codec_name": "h264",
    "@codec_long_name": "H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10",
    "@profile": "High",
    "@codec_type": "video",
    "@codec_time_base": "1/30",
    "@codec_tag_string": "avc1",
    "@codec_tag": "0x31637661",
    "@width": "480",
    "@height": "270",
    "@coded_width": "480",
    "@coded_height": "272",
    "@has_b_frames": "2",
    "@pix_fmt": "yuv420p",
    "@level": "21",
    "@chroma_location": "left",
    "@refs": "1",
    "@is_avc": "true",
    "@nal_length_size": "4",
    "@r_frame_rate": "15/1",
    "@avg_frame_rate": "15/1",
    "@time_base": "1/15360",
    "@start_pts": "0",
    "@start_time": "0.000000",
    "@duration_ts": "122880",
    "@duration": "8.000000",
    "@bit_rate": "183806",
    "@bits_per_raw_sample": "8",
    "@nb_frames": "120",
    "disposition": {
        "@default": "1",
        "@dub": "0",
        "@original": "0",
        "@comment": "0",
        "@lyrics": "0",
        "@karaoke": "0",
        "@forced": "0",
        "@hearing_impaired": "0",
        "@visual_impaired": "0",
        "@clean_effects": "0",
        "@attached_pic": "0",
        "@timed_thumbnails": "0"
    },
    "tag": [
        {
            "@key": "language",
            "@value": "und"
        },
        {
            "@key": "handler_name",
            "@value": "VideoHandler"
        }
    ]
}


  


  I will mention that when I ffprobe the output file the only differences I see are 1) the timing data is different, which isn't surprising, and 2) the output file has

  


      "@has_b_frames": "0",
    "@pix_fmt": "yuv444p",


  


  I'm pretty confident the reader is working okay, because if I write out the data with

  


  skimage.io.imsave('x.png', frame,  check_contrast=False)


  


  it looks good.

  


• I am trying to use ffmpeg to separate audio from video, but after downloading the ffmpeg build I cannot seem to activate it in Power Shell [duplicate]

  19 janvier 2021, par Row Boater

  Ok, look y'all, I am NOT an aspiring programmer. I'm simply trying to separate audio from video of a youtube video I downloaded.

  


  What I've done :

  


  Downloaded YT vid using 4k video Downloader

  


  I downloaded ffmpeg build from https://ffmpeg.org/download.html#build-windows

  


  I downloaded WinZip in order to access the ffmpeg files.

  


  I thought I used winzip correctly, but whenever I paste the command code line recommended to me, ffmpeg -i video.mp4 -c:a pcm_s16le audio.wav, I receive the following :

  


  


  PS C :\Users\user\Videos\4K Video Downloader> ffmpeg -i video.mp4 -c:a
pcm_s16le audio.wav ffmpeg : The term 'ffmpeg' is not recognized as
the name of a cmdlet, function, script file, or operable program.
Check the spelling of the name, or if a path was included, verify that
the path is correct and try again. At line:1 char:1

  


  

  • ffmpeg -i video.mp4 -c:a pcm_s16le audio.wav

  


  • 


      + CategoryInfo          : ObjectNotFound: (ffmpeg:String) [], CommandNotFoundException
  + FullyQualifiedErrorId : CommandNotFoundException



    


  


  


  PS C :\Users\user\Videos\4K Video Downloader>

  


  


  This is all Phoenician to me, but what I take away is that I have not completed some step to fully incorporate the ffmpeg code into my system. I believe that I am not using Winzip correctly.

  


  Thanks for your time.