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  1. Hello,
    Where can I get a list of the options/flags that go in the CODECS line of a m3u8 file?

    For example; in this Apple.com page, it lists the CODECS line.

    HTML Code:
    #EXT-X-STREAM-INF:BANDWIDTH=150000,RESOLUTION=416x234,CODECS="avc1.42e00a,mp4a.40.2"
    http://example.com/low/index.m3u8
    Yet, where can I get a list of those options?


    I am using ffmpeg -i myFile.ts
    to find out the properties of my file.
    How can I turn those properties in what is needed by the CODECS line?
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  2. Open the m3u8 file in a text editor.
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  3. Originally Posted by jagabo View Post
    Open the m3u8 file in a text editor.
    Yeah.
    I am creating the m3u8 file.

    What I need to know is what goes in the CODECS section.
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  4. So you're looking for a list of possible values, not the value for a particular video? Maybe here:

    https://wiki.whatwg.org/wiki/video_type_parameters
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  5. Hm,

    it should be possible to derive the content of the codecs section with the help of ffprobe. E.g.:
    ffprobe -i video.mp4 -select_streams v:0 -show_streams

    Look at the following parameters for the video stream:
    • codec_name (e.g.: h264)
    • codec_tag_string (e.g.: avc1)
    • profile (e.g.: Main)
    • level (e.g.: 40)

    For h264 the part behind "avc1." seems to be a combination of 2 hex values:
    • One for the profile: 42E (Baseline), 4D4 (Main) or 640 (High)
    • One for the level: Convert decimal to hex value, e.g.: 40 => 028 (hex)

    Combination of h264, avc1, Main, 40 => avc1.4D4028

    For the audio it seems to be easier:
    codec_name == aac, codec_tag_string == mp4a, profile == LC => mp4a.40.2


    Have you looked whether you can let ffmpeg create the m3u8 file? Should be easier to let a software do that job.
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  6. Thank you both!!

    That was exactly the information I was looking for!
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  7. Thank you fornit,
    I did the ffprobe -i command, and here is what I got from the list you mention:
    • codec_name=h264
    • codec_tag_string=[27][0][0][0]
    • profile=Main
    • level=30


    The codeg_tag_string is the one I have no idea what's going on with it.

    Any idea if the problem is up-stream when I am re-encoding?

    Originally Posted by fornit View Post
    Hm,

    it should be possible to derive the content of the codecs section with the help of ffprobe. E.g.:
    ffprobe -i video.mp4 -select_streams v:0 -show_streams

    Look at the following parameters for the video stream:
    • codec_name (e.g.: h264)
    • codec_tag_string (e.g.: avc1)
    • profile (e.g.: Main)
    • level (e.g.: 40)
    Quote Quote  



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