Skip to main content

Detect identical & black frame in video with ffmpeg?

Thumbnail creation is a very needed feature for any social networking site. Obviously, ffmpeg is the ideal solution for generating thumbnail.

Problem-1: Detecting identical thumbnails


Fortunately, we have a good solution--libpuzzle. It would be ideal to have a filter in ffmpeg for that.

Problem-2: Detecting black/dark frames


I'm still keenly looking for a solution tied up with ffmpeg. When Google turned no help, Heleena (my wife) solved it by calculating average luminance value of the frame and ignoring the frames based on certain preset threshold value--which worked better at that time.
Labels:

Comments

Post a Comment

Popular posts from this blog

Don't innovate!

Gopinath had a shocking news for me this morning... the site that we were cloning--cloning with additional features and innovations had just released a new version, but with six features taken from our version. Had we released it some days before, we might have grabbed the innovation pride. But... The weirdest thing was that we're forced to clone including the landing page as in their previous version (and that is the reason for this delay), but when we're doing, they switched to our homepage version! Damn... It doesn't stop here. I was pacifying myself and pushing the software to be released by afternoon--at least then to claim the innovation card. Now Kanagavel has another "good news" for me, that we have to "tune" the product to be exactly as in PSD that would take another week to ship...
1 comment
Read more

htmlspecialchars() bug in blogger.com

Found a strange htmlspecialchars() bug in blogger.com The title of my blog is <?php echo 'R. Rajesh Jeba Anbiah'; ?> , but blogger.com doesn't convert the html entities in the title when it spits out. Because of this bug, the title doesn't appear in my blog--browser just treats it as a broken html tag. This bug could have been fixed by using htmlspecialchars() , if it's powered by PHP . Also, noticed that this compose box eats any texts entered such. I gonna report this bug.
1 comment
Read more

Converting PSD with PHP/ImageMagick

After seeing feature rich options in Imagick PECL extension at Mikko Koppanen 's (the author) website and also impressed with ImageMagick 's features, I have decided to use it for the PSD to XHTML conversion website that I'm architecting and managing. Since, the team wants programming help for converting PSD images, I have tried it (documentation is sparse on PSD handling) Converting PSD to PNG/JPEG/etc Note that, flattenImages() is needed for layered/multi-page PSD file. <?php $im = new Imagick('test.psd'); $im->flattenImages(); $im->setImageFormat('png'); $im->writeImage('test.png'); ?> Extracting PSD layers One by one <?php $im = new Imagick('test.psd'); $im->setImageFormat('png'); for ($i = 0, $num_layers = $im->getNumberImages(); $i $im->setImageIndex($i); $im->writeImage('layer' . $i . '.png'); } ?> Note that, there is a better version below In a single call with writeIm...
5 comments
Read more