[FFmpeg-devel] [PATCH] speeding up qt-faststart
Michael Niedermayer
michaelni at gmx.at
Sun Sep 30 21:54:20 CEST 2012
On Sun, Sep 30, 2012 at 07:57:52PM +0200, Jan Ehrhardt wrote:
> qt-faststart is terribly slow when the input file and the output file
> are on a slow disk like a SD card. By increasing the copy_buffer from
> 1K to 32M I decreased the processing time on a sample file from
> 1600 seconds to 4 seconds. The timing difference is during 'copying
> rest of file'.
>
> S:\SD_VIDEO\PRG001>e:\utils\qt-faststart 00005.mp4 5.mp4
> ftyp 0 32
> free 32 8
> mdat 40 13744391
> moov 13744431 141848
> patching stco atom...
> patching stco atom...
> writing ftyp atom...
> writing moov atom...
> copying rest of file...
>
> Execution time: 1576.259 s
>
> S:\SD_VIDEO\PRG001>s:\utils\qt-faststart 00005.mp4 5.mp4
> ftyp 0 32
> free 32 8
> mdat 40 13744391
> moov 13744431 141848
> patching stco atom...
> patching stco atom...
> writing ftyp atom...
> writing moov atom...
> copying rest of file...
>
> Execution time: 3.846 s
>
> Changes to qt-faststart.c are below. c is not ny native language,
> so could somebody check the diff and commit it?
you forgot a free() and its better not to allocate more than needed
ive fixed them and applied the patch
thanks
[...]
--
Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
He who knows, does not speak. He who speaks, does not know. -- Lao Tsu
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 198 bytes
Desc: Digital signature
URL: <http://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20120930/ce3bfc80/attachment.asc>
More information about the ffmpeg-devel
mailing list