[Ffmpeg-devel] Last jpeg patch to support multiple-scan JPEGs
Tue Nov 21 07:21:58 CET 2006
On Mon, Nov 20, 2006 at 06:56:08PM +0100, Cyril Russo wrote:
> Michael Niedermayer a ?crit :
> >On Mon, Nov 20, 2006 at 02:26:34PM +0100, Cyril Russo wrote:
> >>>>Worse, the patch from Kostya doesn't solve the multiple scan JPEG
> >>>>decoding errors as (s)he pretends. The problem is fully unrelated.
> >>>>Interleaved JPEG != Progressive JPEG != Multiple scan JPEG
> >>> kostya posted a second patch which adds Multiple scan JPEG sipport
> >>> by removing 6 lines and chagning 2, while yours duplicates a whole
> >> function (which btw ive complained about in my review and you ignored
> >>> it)
> >>No, it's wrong. Kostya's patch doesn't add multiple scan JPEG support.
> >>He (I make the assumption he is a male)
> >>added progressive support. There is a big difference with multiple scan
Actually, progressive JPEG uses multiple scans too so after integrating it
was easy to add proper support for multiple scans.
> >kostya did send 2 patches one for progressive and one for multiple scan
> >>Again, try to decode the JPEG I've posted before with kostya version, it
> >>will fail.
> >kostya said it works so ill trust him considering that you seem to be
> >a little confused about which patch i speak off
> Ok, let's make things clear. I, and I suppose, all of us too, want to be
> able to decode all standard JPEGs.
> I've found both patch from kostya, and only the last one got applied.
> Anyway, the previous patch from /Mon Nov 20 06:51:15 CET 2006 /doesn't
> work either (the index in the scan is not used for decoding the scan
> while it should)/
No, you have missed it (it was posted in your thread 'Incorrect JPEG decoding
> /Of course you can trust anyone older than me, I'm new here, but I'm not
> new in image processing.
> Again, if you don't want to believe me, believe yourself by compiling
> lastest kostya version, and launch :
> wget http://xryl669ny.free.fr/MyFile000.jpg && mv MyFile000.jpg
> test.mjpeg && ffmpeg -i test.mjpeg -vframes 1 -f mjpeg output.jpg
> You'll get a very beautiful (and uniform) grey picture in output.
Try SVN r7143, it is already there.
> Then, still don't believe me, apply my patch in a separate directory to
> the last SVN version, build, and try the same command line.
> You'll get a good image as output. That's all.
> Then trust who you want, the kostya version works for progressive jpeg,
> not multiple scan jpegs, my version add multiple scan jpeg support
> but as nothing to do with progressive jpeg (it doesn't break anything at
> Anyway, hope you don't take it as a personal attack, what I want is my
> stream correctly decoded.
> If it's already done and working, it's great, whoever made it.
> Currently it's not, so I've added it, I've provided all the materials to
> check if it's working.
> I've corrected the patch so it is like the devs said it should be, so
> what next ?
> Cyril RUSSO
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