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  1. Member
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    hello

    i`m using various Video Convertor for more than 5 years , but after checking many profile and bit rate and setting for generate Mp4 file with highest quality and lowest possible size still i think i miss something

    for example for 1min clip with 640*360 resolution the final mp4 file with medium quality will about 6.5 MB ( logos or subtitle will be pixelize and not great )

    specially when i see some clip with perfect quality and low size i found out that i did something wrong

    for example check this clip

    clup.mp4

    it`s about 2 min and the size is only 6.5 MB !! the subtitle quality is perfect and i even cant get this quality with 1500 bit rate and 12 MB !!


    how can i find out what setting or software they use ?


    Best Regards
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  2. Use mediainfo to see the encoding info

    Writing library : x264 core 112
    Encoding settings : cabac=1 / ref=3 / deblock=1:0:0 / analyse=0x3:0x113 / me=hex / subme=7 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=12 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / constrained_intra=0 / bframes=3 / b_pyramid=0 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=abr / mbtree=1 / bitrate=400 / ratetol=1.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / ip_ratio=1.41 / aq=1:1.00
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  3. There's nothing special about the encoding of that clip. It's x264's medium preset with b-pyramid set to 0 and min/max qp specified:

    Code:
    x264 --preset="medium" --bitrate 400 --b-pyramid 0 --qpmin 10 --qpmax 51 --output output.mkv input.mp4
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  4. Regardless of encoder, there's a few basics you can keep in mind.
    For this example, I'll use Handbrake simply because it's easy enough to adjust through it's GUI interface rather than twiddle with ffmpeg/etc. command line settings (doesn't matter - you can do it by command line if you wish).

    1. Upon loading the video, set the video CROP to take out any black letterboxing above and below the video.
    Almost always, if your filming in a non-16:9 standard ratio, you'll have letterboxing on some masters trying to fit, let's say a 21:9 video to a 16:9 screen.
    Not all masters will have this, so if there's none, skip to the next step.

    2. The default SuperHQ settings get you almost there, but you don't need to worry about selecting that.
    a. FILTERS tab - turn off interlace detection and deinterlace. No need unless you happen to have an interlaced source.
    b. VIDEO tab
    Framerate = match source
    Encoder Tune = Film
    Encoder Profile = HIGH
    Encoder Level = 5.2
    Encoder preset = Very Slow
    Two Pass = on
    Avg Bitrate = set to your desired bitrate

    Two pass along with HIGH 5.2 SLOW or slower is important!

    3. Now, the audio track will gobble up a ton of space if you let it (eg. PCM audio track vs. compressed mp3/aac).
    Typically, you'll want 1 audio track, MP3 or AAC, 128Kbps or so.
    If you give it more kpbs or more tracks, your final file will naturally grow bigger than expected.

    ........

    Now, you've got numerous MP4 encoders out there, some better, some worse in quality at low bit rates.
    https://www.compression.ru/video/codec_comparison/h264_2012/
    Notice the Overall Average Bitrates for the Same Quality chart.
    You'll naturally want to test and use the codecs towards the left of the chart (better = smaller file for same quality).

    At the same time, notice that modern hardware accellerated encoding can produce results under some circumstances better than a software encoder.
    https://devblogs.nvidia.com/turing-h264-video-encoding-speed-and-quality/

    ...

    https://www.streamingmedia.com/Articles/ReadArticle.aspx?ArticleID=119155

    More tips for that extra <5% improvement.
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  5. Member
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    Originally Posted by jagabo View Post
    There's nothing special about the encoding of that clip. It's x264's medium preset with b-pyramid set to 0 and min/max qp specified:

    Code:
    x264 --preset="medium" --bitrate 400 --b-pyramid 0 --qpmin 10 --qpmax 51 --output output.mkv input.mp4
    thanks , i wonder how this clip have this quality with 400Kb bit rates ! i have wondershare uniconveror and any video convertor but none of them get me this quality even in 1500Kb bitrate !
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  6. Member
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    Originally Posted by babygdav View Post
    Regardless of encoder, there's a few basics you can keep in mind.
    For this example, I'll use Handbrake simply because it's easy enough to adjust through it's GUI interface rather than twiddle with ffmpeg/etc. command line settings ...
    wow thank you for spend time and explain everything

    i will try Handbrake , it seems free
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