On Tue, Dec 25, 2012 at 9:44 AM, jdow <jdow@earthlink.net> wrote:
Fernando, any time you edit MEPEG2, 3, 4, etc the image will degrade.
With any of the formats you can get frame accurate editing.

I agree with the theory, and if I worked on broadcast I´d pay attention to that. However, since my point is creating videos for the Internet and sending by e-mail, MPEG2 works fine for me. The point you seem to be missing is that when dealing with different source material, often with LESS resolution than the 720x480 I use as intermediate, when FFMPEG does the conversion it needs to increase the size of the vids, and for this it does interpolation, which actually smoothes the image and reduces artifacts.

The last time I tried to use a mix of the "other formats" as source material, apps either crashed randomly or exhibited odd results when trying to select a given frame as cut point (as if the source material had a full frame every 2-3 seconds, and I wanted to cut at a given fraction of a second, well, KDEnline wouldn´t let me. While when doing cuts on WinFF produced MPEG2 files with "DVD-quality" presets, I never have such problem.

But the last time I did that experiment was in 2009, surely KDEnlive support for other codecs has improved since then. At one point it seemed that KDEnlive´s best consistent feature was the crashing when importing clips. ;-P http://goo.gl/sgJgX

Which takes me back to my initial premise: that there must be something that makes MPEG2 easy to support from the get go for programmers, while dealing with other codecs takes video editing apps several iterations to get right untill all bugs are ironed out.

And yes, you´re right, MJPEG is the best, but again, I personally find the tradeoff of disk space to be too big. On a desktop with a HD several terabytes big, of course disk space is not a concern.

Again, this is not a "definitive guide of how to work with video files from a codec expert´s point of view" just a statement from an end user about a hassle-free method I found by trial and error, and which I use regularly with great results.

YMMV
FC