Transcoded 16:9 files stretched into 4:3

[Amused]

Whenever I transcode files recorded in 16:9 aspect the resulting file is distorted into 4:3. I don't mean blank bars are added at the top and bottom of the picture, I mean the 16:9 image is stretched upwards if you like to 4:3. This never used to happen, it's a sudden thing. I've tried unistalling GBPVR, removing any files left, and starting afresh but the same thing happens.

Can I configure the FFMPEG or are there settings within GBPVR which will keep the aspect ratio?

[Amused]

After further investigation it turns out that the files are file, Gsport shows them as 720*567 which is 16:9 alright yet when opened, each and every files distorts to something that looks like 4:3. I've attached a screen cap to illistrate the problem. This distortion happens will any media player i've tried and makes me think that the problem is still with the file. Presumably it's encoded correctly but the pixed size isn't set to square pixels or something. Any idea on how to correct this, or transcode files which result in the correct ratio?

[HtV]

Gsport shows them as 720*567 which is 16:9 alright

What does gspot say for DAR (Display Aspect Ratio)? I'm not sure but I think hauppauge cards maybe always record 4:3.
What are you transcoding to?
It might be simple to add a 16:9 transcoding line to config.xml.

[Amused]

Gsport give the DAR of both the transcoded avi and original MPEG stream as 1.778 (16:9). The original MPEG recording plays perfect in 16:9 which (being DTV) is what it was broadcast in. The transcoded file however is distorted in both thumbnail icon view and in playing the actual thing, despite seeming to be 720 x 576.

I'm thinking now that it might be my computer that screwing up distorting the aspect and that he avi file is encoded correctly. Trouble is I've no way to tell if I'm right, or how to fix it if I am! That said I've just finished using Dr DivX to trascode a file and although audio is about 2 seconds out of sync (!) the aspect ratio is perfect so maybe it does need a tweak in the config.xml, what would it be?

[HtV]

You could try xvid, see if that helps. I think some players don't recognise the AR-flag right for some codecs, maybe that's the problem.

[Amused]

Transcodeing with other codecs doesn't help, Xvid and WMV files both have the aspect ratio problem. In certain programs, like DivX Player, I can manually select a forced 16:9 ratio but this won't happen as default and DivX Player is the only prog I've found with this option, Media Centre, Media Player, GBPVR etc. still stretch to 4:3.

Sub, can I add a line into the ffmpeg command that will force the aspect ratio to 16:9, or force square pixels or something?

[HtV]

Sub, can I add a line into the ffmpeg command that will force the aspect ratio to 16:9, or force square pixels or something?

As Gspot is stating the DAR = 16:9, I guess the AR-flag is already set.
You could try adding "-aspect 16:9" to the commandline in config.xml.
I guess you'd best add an extra line to config.xml under <CustomFFmpegConversions>

like this:

Code:

<Conversion name="DivX -16:9" cmd="-y -i {SOURCE_FILE} -f avi -ab 224 -ac 2 -acodec mp3 -vcodec mpeg4 -b 1000k [FONT=Courier New][FONT=Verdana]-aspect 16:9[/FONT] [/FONT]-vtag DIVX {DEST_FILE}" targetExtension="divx.avi" />

Backup config.xml first.

Of course you can always use F7 in gbpvr to change the DAR of a show that is playing.

[Amused]

Cool, didn't know about F7, thanks.

I added the aspect command to config.xml and transcoded but no joy. However looking through the logs prior to adding in the -aspect 16:9 command, I have found the following entries:

- S:\Videos\Recorded TV\House\House_20070322_21002200.avi
getSetting(SaveGraphFiles)
setSourceAspectRatio() using autoAspectRatio
video resolution is 720 x 576
unknown source aspect ratio...showing full frame
setSourceAspectRatio() using autoAspectRatio
video resolution is 720 x 576
source has square pixels (AVI etc)

Now this seems to suggest that the pixels are square and that the resolution is 720x526 as GSport said. However the bit that intrigues me is the

unknown source aspect ratio...showing full frame

Now presumably aspect ratio has two parts to play, firstly making sure the frames are kept "in shape" during transcoding and secondly to tell the media app. "this video file is in 16:9" when you open it. Could this "full frame" indicate that the picture is encoded fine but the "master DAR" if you like, is set at full frame?

I've just tried comparing this log to the one from the aspect 16:9 attempt. The 16:9 attempt log stops at
DirectShowPlayerVMR9() initialising...
getSetting(OSDTransparency)
(line 19-20)

[HtV]

I guess when it says 'source has square pixels' that's because it can't/won't read the AR-flag. So the DAR would be 5:4 then (720/576).
You could enter the wanted resolution in the commandline e.g 720x405 (ar=16:9)

Code:

<Conversion name="DivX -16:9" cmd="-y -i {SOURCE_FILE} -f avi -ab 224 -ac 2 -acodec mp3 -vcodec mpeg4 -b 1000k -aspect 16:9 [B][COLOR=red]-s 720x405[/COLOR][/B] -vtag DIVX {DEST_FILE}" targetExtension="divx.avi" />

You can find the ffmpeg documentation here: http://ffmpeg.mplayerhq.hu/ffmpeg-doc.html

[sub]

It always treats an AVI as square pixels, so as HtV says, you'd need to have a resolution like 720x405 for it to be widescreen.