[Ffmpeg-devel] Last jpeg patch to support multiple-scan JPEGs

[Cyril Russo]

Michael Niedermayer a ?crit :
> Hi
>
> On Mon, Nov 20, 2006 at 02:26:34PM +0100, Cyril Russo wrote:
>   
>> Hi,
>>
>>
>>     
>>>> 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 
>> support.
>>     
>
> kostya did send 2 patches one for progressive and one for multiple scan
> jpeg
>
>
>   
>> 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)/

/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.

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 
all).

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 ?

Regards,

-- 
Cyril RUSSO