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• ffmpeg hevc h265 4k 10 bit

  14 juillet 2017, par Ali Jose

  I want to be able to encode 4k videos in TS files having video codec as HEVC at constant bitrate 20 Mbps, dolby audio (2 channel front L & R). This is the spec sheet as provided from my client http://159.8.5.10:3001/download/4k-specs.xlsx Im using this code :

  I used this code at first to produce a sample which conforms to their spec sheet, however the playback was not smooth neither on my side nor on their side :

  ffmpeg -i input.mov -pix_fmt yuv420p10le -c:v libx265  -b:v 19.5M -minrate 19.5M -maxrate 19.5M -muxrate 20M -x265-params "level=6.2" -r 50 -s 3840x2160 -c:a ac3 -b:a 384k -minrate 384k -maxrate 384k -channel_layout 3  output.ts

  the produced sample is found in the following link : http://159.8.5.10:3001/download/two_mns_sample.rar

  The client sent me this sample, he told me it is provided by another supplier and it is approved by their end (it matches their spec sheet and plays smoothly in their broadcast software), the sample is found under the following link : http://159.8.5.10:3001/download/approved-4k.rar

  Then the client sent me another sample, they also said that it is approved by their side (matched their specs and plays smoothly in their broadcast software) found under the following link : http://159.8.5.10:3001/download/approved-4k-2.rar

  When examining well the second approved sample, I noticed that it doesnt meet the spec sheet 100% but the differences are minor (level @ 5.1 instead of 6.2 and dolby 5.1 instead of dolby Stereo... so minor differences) but as they described, it played back smoothly in their broadcast playback. So we can understand from that that they are a bit flexible.

  My 4k source file is an mov Prores 4444, 23.97 fps, 10 bit depth, 444 chroma subsampling, variable bitrate (around 950 Mbps). To find out more info about the input file, please go to this link (MediaInfo txt export) : http://159.8.5.10:3001/download/4k-original.txt

  This is a 2mns sample trimmed clip from my original file (couldnt upload the whole source file since its 800 GB !) : http://159.8.5.10:3001/download/original-2-mns.mov

  I need an ffmpeg code that can generate a sample that complies to their specification sheet and can be played SMOOTHLY in their technical department, it was mentioned they are using 4k playbox technology (maybe airbox but it was not clear, but what we can assure is that they use good instrument for broadcast, they dont go for below average instrument/software), I need to send them samples that they later check and play on their playback system and get approved.

• Fastest way to compress a video in Android

  30 août 2024, par Filnik

  I was wondering what is the fastest way to compress a video on Android. I've tried Transformer by ExoPlayer and is quite slow.

  


  With ffmpegKit and libx264 things are better but the license doesn't allow me to use it in closed source apps. Unfortunately libopenh264 is quite slow and I'm not able to make h264_mediacodec work. Any idea on how to make the mediacodec work ?

  


  This is the code I'm using right now for the tests but it fails with mediacodec (generic error). I've compiled manually FFMpegKit to add mediacodec already.

  


  companion object {
    private const val VIDEO_WIDTH = 1080
    private const val VIDEO_HEIGHT = 1920
    private const val BITRATE_MBS = 7 * 1000000
    private const val COMPRESSION_FILE_NAME = "compression"
    private const val VIDEO_EXTENSION = ".mp4"
}

suspend fun compressVideo(videoUri: Uri): String? = withContext(defaultDispatcher) {
    val tempInputFile = copyUriToFile(context, videoUri)
    val outputFile = File.createTempFile(COMPRESSION_FILE_NAME, VIDEO_EXTENSION, context.cacheDir)
    val outputPath = outputFile.absolutePath

    val cmd = mutableListOf(
        "-y",
        "-i", tempInputFile.absolutePath,
        "-vf", "scale=w=$VIDEO_WIDTH:h=$VIDEO_HEIGHT:force_original_aspect_ratio=decrease",
        "-c:v", "h264_mediacodec",
        "-b:v", "$BITRATE_MBS",
        outputPath
    )

    val session: FFmpegSession = FFmpegKit.execute(cmd.joinToString(" "))

    tempInputFile.delete()

    return@withContext if (ReturnCode.isSuccess(session.returnCode)) {
        outputPath
    } else {
        FirebaseCrashlytics.getInstance().recordException(Exception("FFmpeg compression failed: ${session.allLogsAsString}"))
        null
    }
}


  


• encoder 'aac' not enable exception while processing video for slowing

  2 juin 2016, par Amna Mirza

  While chaging playback speed of video (making video slow) following exception occurs using FFMPEG android java library.

  [aac @ 0x416c26f0] The encoder 'aac' is experimental but experimental codecs are not enabled, add '-strict -2' if you want to use it.