[Ffmpeg-devel] rle encoder problem

Michael Niedermayer michaelni
Tue Apr 3 18:54:57 CEST 2007


On Tue, Apr 03, 2007 at 10:30:06PM +0800, Xiaohui Sun wrote:
> Hash: SHA1
> Hi,
>    Still some problems with rle encoder.
> As in tiff/sgi, the lower 7 bits of the Repetition Count specify the
> real consecutive pixels MINUS 1(a value of 0 implies 1 pixel while a
> value of 0x7F implies 128 pixels). So in rle.c we count up to 128
> pixels. In SGI, this byte simply means just the consecutive bytes, so
> the maximun number of it is 127. I wonder if it is wise to modify the
> rle.c again and set the consecutive pixels upper bound to a configurable
> parameter?

i think simply decreasing the max to 127 is ok

it doesnt affect compression for runs of 0..127 and 130..254, ... or so
so the cases where compression suffers are very few ...


Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Concerning the gods, I have no means of knowing whether they exist or not
or of what sort they may be, because of the obscurity of the subject, and
the brevity of human life -- Protagoras
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: not available
URL: <http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/attachments/20070403/39ef6393/attachment.pgp>

More information about the ffmpeg-devel mailing list