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  1. Member
    Join Date: Apr 2012
    Location: Newcastle Australia
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    Hi can someone help me with converting mkv & flv flies to avi so that when I play them on a screen with a
    Display 7" WQVGA
    Max Res 720x480 @ 30fps and 720x576 @ 25fps, which is the one I use,
    how can I get them to fill the whole screen?

    When I convert them using the 720x576 I get a small 16:9 box that does not fill the screen.
    I donít know what to do. I use AVS Video Converter 7.1 with MPEG4(DivX/Xvid compatible) codec set the frame size to 720x576, same as screen res, but it still comes out smaller.

    Can anyone help please itís so annoying only having half the screen filled and I am a novice at all this.

    Thanks in advanced.

    Disclaimer I donít use it while driving only when parked.
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  2. Set the display aspect ratio, or pixel aspect ratio, to the same as that of the source. And hope your player supports it. Try the attached 720x576, 16x9 xvid avi.
    Attached Files
    Last edited by jagabo; 13th Apr 2012 at 23:04.
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  3. Member edDV's Avatar
    Join Date: Mar 2004
    Location: Northern California, USA
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    WQVGA is nominally 400x240 but here are the aspect ratio variants

    http://en.wikipedia.org/wiki/Graphic_display_resolutions#WQVGA
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    http://www.kiva.org/about
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  4. Member
    Join Date: Apr 2012
    Location: Newcastle Australia
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    Thanks jajabo just did that and no resolution not supported was theresponse. It’s so weird as I am converting to the screen res but they are comingout smaller and if I just convert keeping the videos same size it won’t play.And the Australian distributor of the unit can’t or won’t help they keep sayingit should work.

    Display 7" WQVGA and this Max Res 720x480 @ 30fps and 720x576 @ 25fps, are from the owners manual @ http://www.eclipse-web.com/au/products/navigation/avn/827ga/manuals.html#pageNav click owners manual go to page 220 supported DivX WMA and MP4 standards.

    See this is why I am having a hard tiome at it I am doing what the device says it should do.
    Last edited by Dungogvolts; 13th Apr 2012 at 23:14. Reason: Adding more info
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  5. Maybe it only supports MPG files with 720x576 resolution.
    Attached Files
    Last edited by jagabo; 13th Apr 2012 at 23:22.
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  6. Member
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    Originally Posted by jagabo View Post
    Maybe it only supports MPG files with 720x576 resolution.
    Hey that little video worked, if anything it was just not wide enough but I would put up with that so how did you do it?
    The manual and the support people say it supports avi wmv and mp4
    Click image for larger version

Name:	Before conversion.jpg
Views:	107
Size:	997.7 KB
ID:	11945


    Click image for larger version

Name:	After conversion.jpg
Views:	93
Size:	818.8 KB
ID:	11946
    before image, top, is played in VLC H264 MPEG 4 AVC 640x328 as you can see it has just a little letterbox ex
    after image,bottom, is played in WMP, this time on the right of image, and is 640x480, cant get the codec info, but as you can see it is a lot smaller on the screen.

    I looked at Wikipedia and there is no mention of 720x576 and I have been lead to believe that is standard digita tv format anf hd is higher. sorry it takes me so long to answer but I am slow on the computer and stuff.
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  7. DVDs and the mpeg video therein don't use square pixels. ie a 720x576 DVD can have either a 16:9 or 4:3 aspect ratio. How it displays depends how the video is stretched on playback.

    If you convert to AVI and use 720x576, most players will assume the video in AVI uses square pixels (even if the AVI apsect ratio is correct) so it won't display with the correct aspect ratio. The same thing applies to MP4 although non-sqaure pixel support for MP4s is more likely.

    I don't know anything about the program you're using, but when converting 720x576 DVDs to AVI it's best to resize them to square pixels. For 16:9 DVDs, 656x368 would be a good AVI resolution to use for a portable device, for 4:3, 640x480. If the video contains black bars which are removed when converting though, then the AVI resolutions should change accordingly. Any decent conversion program should do most of the thinking for you. For converting DVDs to AVI, I'd highly recommend using AutoGK.
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  8. Originally Posted by Dungogvolts View Post
    The manual and the support people say it supports avi wmv and mp4
    That doesn't mean it supports the same max frame size with all the different containers/codecs. Xvid, for example, requires more horsepower to decompress than MPEG 2.

    The AVI and MPG are exactly the same. They both encode a 16:9 DAR video into a 720x576 frame. If the player tells you "unsupported resolution" when playing the AVI file it simply doesn't support that frame size when playing AVI files. You'll need to figure out what maximum frame size it does support with AVI and work around that limitation. Say the max is 640x480. You could encode your video at 640x360 with square pixels to get a 16:9 display.

    Originally Posted by Dungogvolts View Post
    before image, top, is played in VLC H264 MPEG 4 AVC 640x328 as you can see it has just a little letterbox ex
    after image,bottom, is played in WMP, this time on the right of image, and is 640x480, cant get the codec info, but as you can see it is a lot smaller on the screen.
    My guess is the software you used put the 16:9 source into a 4:3 (640x480) frame by letterboxing it. Then the player, seeing a 4:3 video, pillarboxed it on the 16:9 display.
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  9. Originally Posted by hello_hello View Post
    If you convert to AVI and use 720x576, most players will assume the video in AVI uses square pixels (even if the AVI apsect ratio is correct) so it won't display with the correct aspect ratio.
    That was true ten years ago. But in my experience most modern players handle PAR/DAR signaling in Xvid AVI files. In any case, the OP's player doesn't support 720x576 AVI files so he'll have to work out something else.

    Originally Posted by hello_hello View Post
    when converting 720x576 DVDs to AVI it's best to resize them to square pixels.
    I would say "safest", not "best".
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  10. Member
    Join Date: Aug 2008
    Location: at 3rd region
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    If prefer 720 under 16:9 ratio, an ideal movie must be sized 720x406 pixel
    If prefer 576 under 16:9 ratio, an ideal movie must be sized 1024x576 pixel

    Please choose which one you like, that's my opinion.
    Leo99
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  11. Avoid using a frame width or height that's not at least mod 4 (an integer multiple of 4). Some decoders are not be able to handle mod 2 or mod 1. Mod 8 or mod 16 are better and safer.
    Last edited by jagabo; 14th Apr 2012 at 12:03.
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  12. Originally Posted by jagabo View Post
    Originally Posted by hello_hello View Post
    If you convert to AVI and use 720x576, most players will assume the video in AVI uses square pixels (even if the AVI apsect ratio is correct) so it won't display with the correct aspect ratio.
    That was true ten years ago. But in my experience most modern players handle PAR/DAR signaling in Xvid AVI files.
    Most software players yes, hardware players, I'm not so sure.

    Originally Posted by jagabo View Post
    Originally Posted by hello_hello View Post
    when converting 720x576 DVDs to AVI it's best to resize them to square pixels.
    I would say "safest", not "best".
    Okay then, safest.
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  13. Member
    Join Date: Apr 2012
    Location: Newcastle Australia
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    Thanks guys, but I am more confused now with all the talk about pixels and stuff. hello_hello thanks for your reply but here is what I am using. Itís an Eclipse AVN827GA media unit that has GPS, radio, Bluetooth and yes a DVD but itís the USB that is causing me all the problems.
    http://www.eclipse-web.com/au/products/navigation/avn/827ga/

    I think I will go back to the seller and start and put pressure on them to get more info from the distributor/manufacture Fujitsu Ten and get them to sort it after all I paid a lot of money and it is not doing what it is suppose to do.

    Thanks for all your help guys.

    Regards
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  14. This page says it does support 720x576 25 fps Divx:

    http://www.eclipse-web.com/au/download/manual/avn827ga_en/avn/contents/_621_90_44.40613.html

    Maybe it doesn't like the Xvid fourcc? Here's the same video with the Divx fourcc.
    Attached Files
    Last edited by jagabo; 14th Apr 2012 at 22:05.
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  15. Member
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    Location: Newcastle Australia
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    Jagabo thanks that worked as did the plain avi 16:9 720x576. As before, if anything, just a little short on the width meaning it did not go to the edges of the screen.

    I know if I download a vid that is say 4:3 format it will not fit the screen and I donít want it to stretch out to fit but the problem I am having is that some when converted to avi divx 720x576 only play in a small box, refer to image 2 in above post, and does not fill the screen. I have just tried wma 720x400 and its looks the best so far.

    I have added some clips of videos playing in the unit itself, I know they are dark, but the image shows how they donít reach the side of the screen. In the first clip, P1000909 the guy dancing, the original video before conversion is MPEG 4 1920x1060 but when converted does not fill the whole screen and depending on how I convert sometimes is just a small box. It is now a wma 700x 400.
    The second clip, P1000910, in its original form before conversion H264 MPEG 4 640x328 and you can see after conversion fills the screen. So this is why I am so confused... that the first one in original form is twice the res but will not fill the screen after conversion but the smaller one will. Oh and the mime still the original video is 1280x720 and it too will not reach the edge of screen.

    I hope I am getting my problem clear enough for you to understand itís so hard to do that via email.
    Again I thank you and everyone else that has responded to my post.
    Am I being to anal about the whole thing?
    Did the attachments work?
    Attached Images  
    Attached Files
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  16. Originally Posted by Dungogvolts View Post
    Jagabo thanks that worked as did the plain avi 16:9 720x576. As before, if anything, just a little short on the width meaning it did not go to the edges of the screen.
    That appears to just be a quirk of that particular device. The 480x272 screen is very close to 16:9 so the image should come very close to filling the screen -- assuming a square pixel display on the device. You might get out a ruler and check to see if it is really a 16:9 display.

    Originally Posted by Dungogvolts View Post
    the problem I am having is that some when converted to avi divx 720x576 only play in a small box, refer to image 2 in above post, and does not fill the screen.
    I told you what the likely problem was earlier. The conversion software is seeing a 16:9 DAR video and letterboxing it in a 5:4 (720x576) frame, not encoding it anamorphically. So the video you created has black borders top and bottom. Then the player sees that 5:4 frame and adds pillarboxing to fill out its 16:9 display. Since the video has black borders at top and bottom, and the player adds black borders to the left and right, you now have big black borders all around a tiny 16:9 picture.

    As was outlined earlier, you have two possible solutions:

    1) Keep the 720x576 frame and convince your conversion software to treat it as anamorphic and to flag the file as 16:9 DAR.

    2) Resize the original to a 16:9 frame size (like ~720x404, or 640x360, ~480x272) and encode as square pixel.

    The former has the benefit that it retains all the resolution of the source and avoids resizing artifacts but wont play back properly on devices that don't support PAR/DAR signaling in Divx AVI files, and the file will require more bitrate (compared to resizing to a smaller frame size)) to retain quality. Of course, the resolution will be lost on the device's low resolution display and the device will introduce it's own resizing artifacts. But if you play the file on a higher resolution device, like an HDTV, it will look very much like the original.

    The latter loses resolution right and creates resizing artifacts right off the bat but produces a file that is compatible with devices that don't support PAR/DAR signalling. In the future, if you play the video on an HDTV it will be noticeably less sharp and have more resizing artifacts than the original.

    If your only concern is watching videos on this particular device, resize to 480x272 (or whatever frame size gives you pixel-for-pixel mapping on the display) and encode as square pixel. Larger frame sizes won't be of any benefit.

    Attached is a 480x272 Divx AVI file. See if your player plays it pixel-for-pixel. It should look like this:

    Name:  sample.png
Views: 3657
Size:  81.3 KB

    Closely examine the black and white lines in the "1" area. You should be able to see each individual line.
    Attached Files
    Last edited by jagabo; 15th Apr 2012 at 12:47.
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  17. Member
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    Jagabo, Again thank you for taking the time to reply. The problem I have now is I do not understand what you are talking about. Ie: DAR video , anamorphic and to flag the file as 16:9 DAR, encode as square pixel, PAR/DAR signaling in Divx AVI files, pixel-for-pixel mapping, Divx fourcc, I guess I should have said I am a novice to all this and when I mention the codec’s ect I get them from the file properties-details. But with your help I have been able to get my videos close enough for me.

    See I assumed that by converting at say 640x360 would give me a smaller picture and therefore my confusion in trying to get them bigger but not able to play above the 720x576. As said I am a novice at all this but have played around and found a setting that looks like it will work for me and that I have to convert videos one at a time and not batch convert.

    I worked with PAL analogue TV starting in the black & white days and have been out of the game for 20 odd years and only just dipped my toe into the digital world and with so many formats ect it all gets a little confusing.

    But I thank you for your time and patients and without it who know what I would be turning out.
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  18. Originally Posted by jagabo View Post
    Avoid using a frame width or height that's not at least mod 4 (an integer multiple of 4). Some decoders are not be able to handle mod 2 or mod 1. Mod 8 or mod 16 are better and safer.
    What would the symptoms be, what would not work good, tearing would be introduced ?
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  19. DAR = display aspect ratio, the final shape of the picture you see. With DAR signalling the video file tells the player to display the video with the indicated DAR regardless of the frame size. For example, PAL DVD uses a 720x576 frame size for both 4:3 and 16:9 display. With DAR signaling any frame size can be displayed at any display aspect ratio (within limits of a particular devices, codec, etc.).

    "Square pixel" means that the display aspect ratio is the same as the frame size aspect ratio. For example a 640x480 (a 4:3 ratio) frame size will result in a 4:3 display, a 640x360 frame size will result in a 16:9 display.

    PAR = pixel aspect ratio, the shape of individual pixels. If individual pixels aren't square the display aspect ratio will not be the same as the frame size aspect ratio. For example, a 480x480 frame size can specify that pixels should be 1.33 times wider than they are tall -- resulting in a 4:3 DAR.

    The general relationship between DAR, PAR and frame aspect ratio is:

    DAR = PAR * FAR
    displayed aspect ratio = pixel aspect ratio * frame aspect ratio
    In the case of square pixels (1:1 PAR) DAR = 1/1 * FAR, DAR = FAR.

    No matter what frame size you encode your video at your player will display it with a 480x272 screen. A 720x576video will be displayed the same size as a 480x272 video if they both are 16:9 DAR. And the two probably won't look much different. Even a small frame size like 240x136 will fill the screen (assuming the player upscales it), but it won't look as sharp.
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