Re: [Mjpeg-users] searching for black frames in an mjpeg stream (adv editing)

2004-05-25 Thread Brian J. Murrell
On Tue, 2004-05-25 at 17:58 +0200, Ronald Bultje wrote: > > The issue here is that mjpegtools doesn't provide any way of doing this. > You'll have to dive into libjpeg internals yourself to get this done. It's > not that hard, but it's icky, if you know what I mean. Yeah, and way over my head. I

Re: [Mjpeg-users] searching for black frames in an mjpeg stream (adv editing)

2004-05-25 Thread Ronald Bultje
Hi, On Tue, 25 May 2004, Matto Marjanovic wrote: > The first coefficient of each macroblock in JPEG is the DC value for > the macroblock, right? Maybe you don't have to completely decode any > scanlines at all. You'd have to decompress/unpack enough to recover > the coefficients for blocks to

Re: [Mjpeg-users] searching for black frames in an mjpeg stream (adv editing)

2004-05-25 Thread Matto Marjanovic
>> You you have to take a look at the center, oft the first field or >> something like that.=20 > >Yeah, funny enough, the black frame search I did in mplayer looked at >the centre of the frame and worked it's way towards the top and bottom >of the frame for just that reason, however, that d

Re: [Mjpeg-users] searching for black frames in an mjpeg stream (adv editing)

2004-05-24 Thread Brian J. Murrell
On Mon, 2004-05-24 at 18:09 +0200, Bernhard Praschinger wrote: > Have you also taken a look at the lav2yuv secenlist feature ? Not beyond having seen is presence in the usage: statement for lav2yuv when I was digging through the code to see just how difficult it would be. > There lav2yuv splits t

Re: [Mjpeg-users] searching for black frames in an mjpeg stream (adv editing)

2004-05-24 Thread Bernhard Praschinger
Hallo > I once wrote a filter for mplayer that searched for black frames. The > idea was to find the 1 or more frames that most frequently sit between > "content" and the commercials. Have you also taken a look at the lav2yuv secenlist feature ? There lav2yuv splits the inputfile into several sce