Picture show and pixel size

CrazyRussian wrote on 3/10/2003, 11:46 AM
Pre reading for the question:
pixels on computer monitors are square, pixels on TVs are "tall", in other words, computer monitor with standard ratio 4:3 of NTSC video has resolution 480x640, TVs though, have resolution 480x720, same 4:3 ratio. This is possible becase TV pixels are not square, they are rectagular, height is greater than width. So, if one would take a picture of a perfect circle using digital camera, it would look perfectly round on the computer monitor, but as upright oval on the NTSC TV once authored and put onto DVD. "Manual" solution to get correct pictures (not streched up) onto DVD is to create image on the computer with 720x540 resolution, then resample it to 720x480, making image to look squashed, then put it through authoring applicatoin and onto DVD.
And here comes the question:
How does DVDA addresses that? If one would take a picture of perfectly round cirlce, then import that image (not changing image size) into DVDA creating picture show, will that cirlce look perfectly round once played on a regular DVD player?

Comments

SonyTony wrote on 3/11/2003, 10:20 AM
Some file formats (such as MPEG for video) have aspect ratio information stored in them. For those formats DVDA uses the stored aspect ratio when rendering video frames. For file formats that do not have pixel aspect ratio stored in them DVD Architect assumes a source pixel aspect of 1.0 (computer pixels). This includes most still image formats.

When DVD Architect renders, it looks at the aspect ratio of the output (NTSC, PAL, etc...) and appropriately stretches the source video frames to look right on the output device.

As such, if the circle in your JPEG picture looks like a circle on the PC, it should look like a circle once it is burned onto a DVD using DVD Architect. (To see this in action, you can enable or disable the "Simulate Device Aspect Ratio" option in the "Options" menu. When enabled, your preview shows the image as it will be seen on the TV screen.)