I need some help editing a couple .avc files.

[Agent86]

I'm going to try pursuing re-encoding using avisynth, but in the meanwhile I'm curious if I can go a different route.

I have some .vobs I converted into AVC format videos for my PSP. They look amazing, however, they are too dark.

Is there any way to adjust the color brightness, sharpness, saturation, hue, etc. on an AVC file? Is there a program that can do this without reconverting/compressing it?

[unskinnyboy]

Had you been viewing these on a PC, you could have achieved what you wanted using ffdshow or a decent software player like BSPlayer. But on a PSP, unless the device offers the ability to change all these when viewing the video (and I am guessing it should, if not sharpness, at least brightness/saturation/contrast etc), you are SOL. Re-encoding it is.

[Agent86]

So there's no way to change the inherent brightness on a movie and save it as another file, as you would with a photo and a basic photo editor? (I say this because, no, the PSP does not have such functions.)

[Sharktooth]

No way unless the player supports it or you'll need to re-encode using a brightness/gamma filter.

[unskinnyboy]

So there's no way to change the inherent brightness on a movie and save it as another file, as you would with a photo and a basic photo editor? (I say this because, no, the PSP does not have such functions.)
What do you think happens when you increase the brightness of a photograph and resave it as another file? It is getting re-encoded, of course. It isn't evident to you because the re-encode happens quite fast. Consider your movie as being composed of thousands of such photographs (frames) one after the other - every single one of them would get re-encoded. And because of the sheer number of such frames, the elapsed time becomes quite tangible.

Clear?

[Agent86]

Sure, I get that. I was just hoping it was possible with an AVC source file, as opposed to taking the .vob file and writing a script to reconvert it with a brightness filter, which I honestly have no clue how to do and haven't gotten any closer to figuring out in the last couple weeks I've been working on it.

[unskinnyboy]

To get optimal quality, it is always better to encode from the original source again. When you re-encode an already encoded file, there will be a significant quality loss. You just need to repeat whatever you had done earlier to get this AVC file, with the difference that this time you will need to do some filtering to fix the brightness/color issues. Even if you were to re-encode this AVC file again, you can't do without the filtering step.

What you are attempting to do is a quite simple process and there are tons of GUIs/tools available for that. The search button is your friend.

[Agent86]

I've been searching for such an app for quite some time. If it's an easier process than writing an avisynth script and putting it in PSP Video 9 or a similar app, please enlighten me.

I have yet to find any one application where you can: Take a .vob file, and convert it to a PSP-formatted .avc file, editing the brightness/contrast in the process.

[unskinnyboy]

What I meant to say was that there are tons of GUIs/tools which will take an avisynth input and output an avc video. Your PSP video is nothing but an MPEG-4 compatible video with a specific resolution, a specific bitrate limit & a few other restrictions. You could make such a video using any appropriate tool if you know the exact specifics your PSP supports.

PSP Video 9 supports Avisynth input, so just make your avs with the necessary filtering and feed it to PSP Video 9 (but I see that you already have another thread open on this and received some advice too). MeGUI also has a PSP video profile (PD-PSP from the list), if you want to give it a go.

[Blue_MiSfit]

Ya... Time to learn some AviSynth :) Very simple. Use DGIndex to index your VOBs and make a d2v. Load this d2v - something like this


#Load D2V
mpeg2source("...\movie.d2v")

#Adjust levels to whatever you want - see the AviSynth manual for #details on the levels function
Levels(...)

#Resize to psp native resolution (not sure what it is)
lanczosresize(x,y)


Something basic like that should give a reasonable avisynth script that can be fed to an encoder like MeGUI or whatever you want to use.

Good luck

~MiSfit