Video Conversion Tutorial

[Smurf]

I really disliked the instructions contained within the wiki (not to mention the program used) so I wrote up a much longer and much more complete tutorial using VirtualDub and XviD. It also includes some nice settings for keeping quality while keeping small sizes (includes sample file at the end of the tutorial).
Link:
http://halffull.net/convert/

It should be really easy to understand for most anyone.


PS-
Fear And Loathing rocks.

 

[sand_man]

Fear And Loathing rocks.

​

Yes it certainly does
Good work Smurf.

 

[bazuka]

I am going to do a similar tutorial for Mac OS X when I get home in a couple days. I feel the need to contribute something to the community.

 

[Michael]

Hey bazuka a tutorial for mac would be very helpful for me so please do

 

[mth411]

On the mac you can use the converting program from the gp32, as it used xvid or divx, and gave a fps option.

Igp32
http://www.gp32x.de/cgi-bin/cfiles.cgi?0,0,0,0,16

There is source available for it, it uses mplayer/mencoder as the backend, and is mostly just an easily edited script for the conversion part.

 

[gaijinflyer]

I new to this but found ffmpegX from versiontracker.com.

I'll give it a try for encoding on OS X.

 

[Jurrasic]

Good info! Thank you for this.

 

[diablo2]

Holy crap! Nice job.

 

[Phil]

I'd just use pocket Divx encoder. It makes everything SO simpler.

While VirtualDub gives you alot more control PDE is fast and easy.

 

[jmetal88]

I know a much easier way.... rip it using SmartRipper (if from a DVD) and convert it with PocketDivXEncoder. 2-step, very hard to mess up.

EDIT: Beaten to it.....

 

[bazuka]

ffmpegX is what I use on the mac to encode, but it can be testy with the version differences.

 

[geniv]

Question. I don't have the gp2x yet.

do divx files at DVD type resolution. just run on the gp2x?

because I got alot of movies (dvd rips) that I got off the internet and divx of tv shows like LOST, 24, SUPERNATURAL etc.. and they are like high quality.

if I just put them on the SD card without conversion will the gp2x be able to play them at such a high bitrate/ resolution ?

yeah I know it's a waste of space for high res on the gp2x 320x240 screen but I have large SD cards and dont' want the hassle of conversion. I just want to put it on the sd cards and watch the movies.

 

[Kayday]

THey should run fine. I also don't feel like reencoding so I just toss some tv shows on the SD card and they all work. Even big files that are 700MB+ work. I usually only reencode if the volume is too low or video is dark.

 

[leamington]

Nice tutorial, Smurf - although it's maybe worth noting that the GP2X movie player will crop the bottom of a 320x[whatever] video if it's dimensions are not exact multiples of 16... so only the top 320x128 pixels of your 320x136 example are displayed.

Maybe this will be fixed with future updates from GPH but in the meantime you can ensure all of your video frame is displayed by using the "Expand frame and letterbox image" option in VirtualDub's resize filter to add black borders at the top and bottom to increase the height of the output video to the next multiple of 16 - ie. choose 320 and 144 for the width and height.

 

[Morwynd]

Nice guide.

One point: you mention playing the file in VLC player to figure out the frame rate, but this is possible to find out right in VirtualDub. Just to to "File Information" in the File menu and it will give you the stats for the video and audio streams.

Another way is to go to Frame Rate in the Video menu; at the top it will say "No change (current: xx.xxx fps)"

 

[Prothall]

The simple guide for Linux or Windows:

1. Download and install Avidemux.

2. Run Avidemux and open the file to be converted.

3. If Avidemux says anything (like "this appears to be VBR audio") follow the instructions in the pop up (in the above case, go to Audio>Build VBR Time Map (remember, only use CBR on the GP2X!)

4. On the left side of the application, click the "V Process" and "A Process" buttons. Make sure the output format is AVI. You may choose what codecs you like, though I am currently using - with great success - the Linux defaults of LameMP3 and LavCodec MPEG.

5. Click "Configure Audio". Select an appropriate bitrate, and change the stereo/mono quality if you like. I currently use Mono at 64 kbps for most things. (The difference between stereo and mono can be quite dramatic, if not the greatest factor.)

6. You do not need to click "Configure Video" - using that you could set a video bitrate, but this results in much lesser quality than the quantizer in action scenes without saving much space. (do note, if you have a Black and White film, checking "greyscale" under Configure Video will save you a great deal of space.)

7. Click "V Filter" and select MPlayer Resize. Adjust settings so that the greatest dimensions fit on the GP2X screen (320 wide by 240 high).

8. If you like, still on the V Filter screen, downsample the framerate. Rates as low as roughly twelve may be acceptable; a rate like 20 is not differentiable from the usual (nearly 24 for NTSC), though how much space this saves is unknown. In the interest of conversion time, it's probably best to skip it.

9. Click "Save" and give your file a name. Note that the AVI suffix is not automatically apended; add it yourself.

NOTE: Softsubs are not picked up by this program. It can read OGM files but not MKV files. I am not familiar with saving Dual audio files using it (though I have converted dual audio files to files with only the audio I want easily - when opening a dual audio file you should be given relevant options.).

I hope this has been of service. on my machine encoding an anime episode takes anywhere from 10 to twenty minutes, usually on the short side. Of course, I've got a 1.8GHz 2GBRAM maguffin and I'm not playing UT while converting.