[FFmpeg-devel] [PATCH] Support BMP files that do not properly align lines.

Reimar Döffinger Reimar.Doeffinger at gmx.de
Tue Jan 27 21:25:29 CET 2015


On Tue, Jan 27, 2015 at 09:50:26PM +0100, Michael Niedermayer wrote:
> On Tue, Jan 27, 2015 at 06:38:22AM +0100, Reimar Döffinger wrote:
> > On 26.01.2015, at 22:49, Michael Niedermayer <michaelni at gmx.at> wrote:
> > > On Mon, Jan 26, 2015 at 08:21:16PM +0100, Reimar Döffinger wrote:
> > >> Quite a few programs missed that detail of the spec
> > >> (including old versions of FFmpeg I believe) and when
> > >> we would otherwise fail anyway it seems worth a try
> > >> to us a simple byte-aligned stride instead.
> > >> 
> > >> Signed-off-by: Reimar Döffinger <Reimar.Doeffinger at gmx.de>
> > >> ---
> > >> libavcodec/bmp.c | 10 +++++++---
> > >> 1 file changed, 7 insertions(+), 3 deletions(-)
> > > 
> > > should be ok, do you have a file that needs this ?
> > 
> > Yes, the game X-Wing Alliance creates such files as screenshots if you hack to use affected resolutions.
> > You can discuss whether they forgot about it or left it out because it doesn't "officially" support such resolutions.
> > Or do you mean because you'd like a test-case? That should be possible to get.
> 
> i wanted a testcase, yes, but its not really important if its correct

Here:
http://ffmpeg.org/~reimar/flightscreen16.bmp
Firefox btw. doesn't refuse to open it like FFmpeg, but renders it
distorted...
Not sure which is better, though the exact file sizes could be used
to decide between these if someone wanted to support partial bmp
files in the future (which is quite reasonable, too, I think)...


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