Creating NTSC Stills & Subpictures for Multi Aspect Ratio Menus.

Aspect Ratios

To accommodate the difference between computer Monitors and TV Screen pixel shapes, images should be created using relative image sizes and then scaled to the appropriate aspect ratio prior to authoring.
This is done by using:
720 x 540 for 4:3 mode
854 x 480 for 16:9 mode.
The picture will look proportional to the way that it will be displayed on the television monitor.  This allows the graphic artist to create menu graphics while being able to view them proportionally.  After the files are finished they must be scaled for use in the authoring process.  Using the Apply Image option in Photoshop, the image should be changed to a resolution of 720 x 480 ( do not constrain proportions).

4:3 Subpictures

4:3 menus also need a subpicture overlay graphic for creating highlight areas, etc.  The subpicture overlay should be created as a second layer in Photoshop, allowing you the potion to turn it on and off.  Simply turn off all layers other than the subpicture overly and save it as a stand alone file.  ( Pict of Tiff)  The two images will now align when imported into DVD authoring application.  (The image should be scaled to the correct aspect ratio prior to saving the subpicture layer.)

16:9 Subpictures

Creating subpicture layers for 16:9 menus is the same as for 4:3 menus.  Simply, start with an image size of 854 x 480 while creating the graphic, and then scale it to 720 x 480 before importing it into DVD authoring application..  The subpicture and still will align in 4:3 mode but will look elongated since it is anamorphic.

Letterbox and Pan Scan Subpictures

Depending on how a SVS is authored and the Player configured, an Anamorphic image can be scaled for use in PanScan or Letterbox formats. The subpicture layer IS NOT scaled like the background image.  To accommodate for this, separate Subpicture layers need to be created for Letterbox and PanScan formats.

Creating subpictures for Letterbox formatting:

    1.Create the proportionally correct image in the 854 x 480 ( letterbox) resolution document.
    2. Paste this image into a 854 x 640 size document.
    3. Align the image vertically exactly in the middle of the image window.
        ( Photoshop will align the 854 x 480 image exactly when it is pasted into the new 854 x 640 image window).
    4. Create the Subpicture layer so it aligns properly with the background image.
    5. Change the image resolution to 720 x 480 ( do not constrain proportions), and save the Subpicture layer as the
        LetterBox subpicture file.

Creating subpicture for Pan-Scan formatting:

    1.Paste the proportionally correct 854 x 480 image into a 640 x 480 resolution document.
    2. Align the image exactly in the middle Horizontally and Vertically..
    3.Create the subpicture layer where it aligns properly with the Still image.
    4. Change the image resolution to 720 x 480 (do not constrain proportions) and save the Subpicture layer as the
        Pan-Scan subpicture file.

These Files can now be used for the appropriate format.

Creating PAL Stills & Subpictures for Multi Aspect Ratio Menus.

Aspect Ratios

To accommodate the difference between computer Monitors and TC screen pixel shapes images should be created using relative image sizes and then scaled to the appropriate aspect ratio prior to authoring.
This is done by using:
768 x 576 for 4:3 (Square pixel)
1024 x 576 for 16:9 (Square pixel).
The picture will look proportional to the way that it will be displayed on the Television monitor.  This allows the graphic artist to create menu graphics while being able to view the proportionally.  After the files are finished they must be scaled for use in the authoring process.  Using the Apply image option in Photoshop, the image should be changed to 720 x 576 (do not constrain proportions).

4:3 Subpictures

4:3 menus also need a subpicture overlay graphic for creating highlight areas, etc.  The subpicture overlay should be created as a second layer in Photoshop, allowing you the option to turn it on and off.  Simply turn off all layers other than the subpicture overlay and save it as a stand alone file.  (Pict or Tiff)  The two images will now align when imported into DVD authoring software.  (The image should be scaled to the correct aspect ratio prior to saving the subpicture layer.)

16:9 Subpictures

Creating subpicture layers fir 16:9 menus us the same as for 4:3 menus.  Simply, start with an image size of 1024 x 576 while creating the graphic, and then scale it to 720 x 576 for importing it into Producer.  The subpicture  and still will align in 4:3 mode but will look
elongated since it is anamorphic.

Letterbox and Pan Scan Subpictures

Depending on how a DVD is authored and the Player configured, and Anamorphic image can be scaled for use in PanScan or Letterbox formats.  The subpicture layer IS NOT scaled like the background image.  To accommodate for this, separate Subpicture layers need to be created for Letterbox and PanScan formats.

Creating subpictures for LetterBox formatting

    1. Create the proportionally correct image in the 854 x 480 ( Letterbox) resolution document.
    2. Paste this image in a 1024 x 768 size document
    3.Align the image vertically exactly in the middle of the image window.
       (Photoshop will align the 854 x 480 image exactly when it is pasted into the new 1024 x 768 image window.)
    4. Create the Subpicture layer so it aligns properly with the background image.
    5. Change the image resolution to 720 x 576 ( do not constrain proportions), and save the Subpicture layer as the
        Letter_Box subpictue file.

Creating subpictures for Pan-Scan formatiing.

    1.Paste the proportionally correct 1024 x 576 image into a 768 x 576 resolution document.
    2. Align the image exactly in the middle Horizontally and Vertically.
    3. Create the subpicture layer where it aligns properly with the Still image.
    4. Change the image resolution to 720 x 576 (do not constrain proportions) and have the Subpicture layer as the
        Pan-Scsan subpicture file. 

These Files can now be used for the appropriate format.

Modern video encoders (like MPEG-2, H.264, On2, VP6, Sorenson Spark) work by dividing the video frame into blocks. The entire frame becomes a grid of blocks, 16 pixels high and 16 pixels wide. These 16x16 blocks are called macroblocks. When you encode video, you have to use height and width values that are multiples of 16. When the height or width doesn't divide cleanly into 16, the video encoder has to make up extra "garbage" information for the edges of the frame. This increases the file size or decreases the video quality, depending on whether you're targeting a constant quality or a size/bitrate. While you can use any width and height in your encoding settings, non-optimal dimensions can result in poor image quality and reduced frame rate. For the best playback, it is strongly reccomended to use width and height playback dimensions that use a multiple of 16 (best), 8 (better), or 4 (good). You can use our on-line video size calculator to define optimal encoding and playback dimensions for your video.