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cite="mid:CABRG=Bx9dt9+L5Ck2u9mV1Z685jNc7vPUVj+VFBR9Fn7ohrbow@mail.gmail.com"
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<div class="gmail_extra">But a frame rate conversion is going to
have a negative impact on picture quality. Everything else
in Mike Stucky's script is optimized for quality ('slow'
preset and crf of 18), so I doubt he would want to do that.
If broken seektables are the problem, I would think it would
be a far better solution to just rebuild the seektable(s) if
necessary after the conversion as part of the script... <br>
<br>
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<div class="gmail_extra">- Dave<br>
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A seektable is not used for h264 videos. After conversion, you
need to clear the entries in the seektable ( rebuilding it will
clear it ). <br>
<br>
To improve the ability to seek, a smaller GOP can be used so the
keyframes are closer. By default for ffmpeg/x264 is a key every
250 frames, or every 8.3 seconds. If you go lower, such as 50
frames, the keys are 1.6s, this makes the seeking much more
accurate. This does come at the expense of higher bitrate. <br>
<br>
You can also play with scenecut thresholds, which also determine
when keyframe are used. I normally set this to 60, which also
produces sightly more keyframes. Increasing this value lowers the
threshold of when keyframes are generated, based on the frame
content and how much of the frame is changed.<br>
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text-indent: 0px; text-transform: none; white-space: normal;
widows: 1; word-spacing: 0px; -webkit-text-stroke-width: 0px;
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--keyint <integer> (x264)<br>
<b>-g <integer></b><span class="Apple-converted-space"> </span>(FFmpeg)<br>
Keyframe interval, also known as GOP length. This determines the
maximum distance between I-frames. Very high GOP lengths will
result in slightly more efficient compression, but will make
seeking in the video somewhat more difficult. Recommended default:
250
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background-color: rgb(255, 255, 255);">
--scenecut <integer> (x264)<br>
<b>-sc_threshold <integer></b><span
class="Apple-converted-space"> </span>(FFmpeg)<br>
Adjusts the sensitivity of x264's scenecut detection. Rarely needs
to be adjusted. Recommended default: 40<br>
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If you plan on streaming the video to a mobile device, you also
want to move 'moov atom' to the beginning of the file, so it can
utilize faststart. This allows the video to start streaming before
the entire file is transferred. ( -movflags faststart ).<br>
<br>
Dennis<br>
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