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<blockquote data-quote="Frodo" data-source="post: 69195" data-attributes="member: 10277">Hi!Great idea on the aspect ratio'sI think it will be simple to add support for this once we figured out the math. Since i'm no expert on aspect ratio stuff i would like to ask you guys to help me a bit with it;-)To calculate a correct aspect ratio we need to look at the following parameters:1. The screen display width/height. The screen displaysize is the entire width/height on which we can present the video. In fullscreen this is simply the entire mediaportal window, but in preview mode its much smallerExample when desktop is set to 1024x768 then in fullscreen mode the screen display size is also 1024x7682. The video width/heightThis is the width/height of the video itself. Some examples&nbsp; PAL&nbsp; &nbsp; = 720x576&nbsp; NTSC = 704x480&nbsp; HDTV 1080i&nbsp; = 1920x1080&nbsp; HDTV 720p&nbsp;&nbsp; = 1280x720Offcourse these are just examples, the video can be any size. 3. The video aspect ratioThe aspect ratio in which the video was encoded. example For PAL this can be 4:3 or 16:94. The pixel aspect ratioThis one is a bit harder to understand.On VGA screens a pixel has the same width/height so its aspect ratio is 1:1 However on a TV screen a pixel is however not 1:1, if i remember correctly its 768/767. On a plasma/lcd screen it maybe different as well5. The desired aspect ratioThe aspect ratio the user desires. Normally this will be the same as 3. The video aspect ratio, but for example if you you choose stretch mode, then the desired aspect ratio is different then the video aspect ratioNow if suppose we the 5 parametersWe then must come up with a formula which gives me 2 rectangles:1) the rectangle which specifies which region of the video source should be displayed2) the rectangle which specifies where on the screen the rectangle in 1) should be displayedThe video source rectangle specifies the left/top,width/height of a rectangle which should be copied.Example:zoom mode. In this case you need to copy a region of the video source and not the entire video source so if video is 720x576 then we might copy (10,10)-(700,557)The rectangle onscreen tells us where exactly on screen we're gonna display the video region copied in step1so if we again have the&nbsp; (10,10)-(700,557) then we might copy that to(0,100)-(1024,758) which produces a 100pixel black bar on the top &amp; bottomSo... who can give me the math??Here are some tasks:1)screen display&nbsp; &nbsp;&nbsp; : 1024x768video&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; : 720x576video AR&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; : 4:3pixel AR&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; : 0.9 : 1desired AR&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; : 4:3video source rect : ???display rect&nbsp; &nbsp; &nbsp; &nbsp;&nbsp; : ???2)screen display&nbsp; &nbsp;&nbsp; : 800x600video&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; : 1920x1080video AR&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; : 16:9pixel AR&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; : 0.75 : 1desired AR&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; : 14:9video source rect : ???display rect&nbsp; &nbsp; &nbsp; &nbsp;&nbsp; : ???Frodo</blockquote>

[QUOTE="Frodo, post: 69195, member: 10277"] Hi! Great idea on the aspect ratio's I think it will be simple to add support for this once we figured out the math. Since i'm no expert on aspect ratio stuff i would like to ask you guys to help me a bit with it;-) To calculate a correct aspect ratio we need to look at the following parameters: [b]1. The screen display width/height. [/b] The screen displaysize is the entire width/height on which we can present the video. In fullscreen this is simply the entire mediaportal window, but in preview mode its much smaller Example when desktop is set to 1024x768 then in fullscreen mode the screen display size is also 1024x768 [b]2. The video width/height[/b] This is the width/height of the video itself. Some examples PAL = 720x576 NTSC = 704x480 HDTV 1080i = 1920x1080 HDTV 720p = 1280x720 Offcourse these are just examples, the video can be any size. [b]3. The video aspect ratio[/b] The aspect ratio in which the video was encoded. example For PAL this can be 4:3 or 16:9 [b]4. The pixel aspect ratio[/b] This one is a bit harder to understand. On VGA screens a pixel has the same width/height so its aspect ratio is 1:1 However on a TV screen a pixel is however not 1:1, if i remember correctly its 768/767. On a plasma/lcd screen it maybe different as well [b]5. The desired aspect ratio[/b] The aspect ratio the user desires. Normally this will be the same as 3. The video aspect ratio, but for example if you you choose stretch mode, then the desired aspect ratio is different then the video aspect ratio Now if suppose we the 5 parameters We then must come up with a formula which gives me 2 rectangles: 1) the rectangle which specifies which region of the video source should be displayed 2) the rectangle which specifies where on the screen the rectangle in 1) should be displayed The video source rectangle specifies the left/top,width/height of a rectangle which should be copied. Example:zoom mode. In this case you need to copy a region of the video source and not the entire video source so if video is 720x576 then we might copy (10,10)-(700,557) The rectangle onscreen tells us where exactly on screen we're gonna display the video region copied in step1 so if we again have the (10,10)-(700,557) then we might copy that to (0,100)-(1024,758) which produces a 100pixel black bar on the top & bottom So... who can give me the math?? Here are some tasks: 1) screen display : 1024x768 video : 720x576 video AR : 4:3 pixel AR : 0.9 : 1 desired AR : 4:3 video source rect : ??? display rect : ??? 2) screen display : 800x600 video : 1920x1080 video AR : 16:9 pixel AR : 0.75 : 1 desired AR : 14:9 video source rect : ??? display rect : ??? Frodo [/QUOTE]

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