Converting .mov or .avi to DVD

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i am trying to convert some avi and mov files to DVD (vob). they are all 720 x 480, and i think from ntsc sources.

using ffmpegx's DVD presets, both ffmpeg and mpeg2, i get a slight letterboxing, even though i've selected DVD or 4:3 autosize and DVD encoding profile (in the video and options) tabs. there is no letterboxing when i view the files in quicktime player, mpeg streamclip or vlc.

please could someone offer some advice so that i can make the best quality, correct ratio DVDs from these files ?

thank you,

mark

[Case]

The DVD mpeg2enc preset activates the Letterbox option in Options by default. Deselect that checkbox to encode without letterboxing.

The DVD ffmpeg preset can decode with QT. When set, it also activates a Letterbox checkbox in Options. Deselect that last checkbox to encode without letterboxing.

If your source clips are not exactly 4:3 or 16:9, then you'll be needing letterboxing, as DVD only supports 4:3 or 16:9 aspect ratios.

[webstar]

case

thanks for your help. it's not the presence of the letterbox that worries me, more the fact that it looks like ffmpegx has changed the ratio of the image (making the letterbox necessary). is this possible ?

this happens even when i set the extact same pixel sizes for the DVD as the source file. could it be something to do with different pixel shapes ? i'm not so technical, but isn't there a possible difference between square and rectangular pixels ?

mark

[Case]

it looks like ffmpegx has changed the ratio of the image (making the letterbox necessary). is this possible ?
this happens even when i set the extact same pixel sizes for the DVD as the source file. could it be something to do with different pixel shapes ? i'm not so technical, but isn't there a possible difference between square and rectangular pixels ?

It is possible that ffmpegX changes the aspect ratio. It may presume square pixels for the source file (MOV, AVI) and will use rectangular pixels for the DVD encoding.

MOV files can have rectangular pixels, but most use square, as that is the logical choice for desktop computer viewing. AVI files can have rectangular pixels, but most use square, and when they have rectangular pixels, there is very little support for those custom ratios in players.

The 720x480 size of the source may be a hint that the source was to be viewed at 4:3 (or 16:9) and not (720 / 480 =) 3:2, as the 720x480 resolution matches SDTV, as found in digital broadcast, DVD and DV. But only the viewer can confirm that. It's also possible that the source file was to be viewed at a.r. 3:2, in which case letterboxing is needed for DVD encodings.

[webstar]

The 720x480 size of the source may be a hint that the source was to be viewed at 4:3 (or 16:9) and not (720 / 480 =) 3:2, as the 720x480 resolution matches SDTV, as found in digital broadcast, DVD and DV. But only the viewer can confirm that. It's also possible that the source file was to be viewed at a.r. 3:2, in which case letterboxing is needed for DVD encodings.

i don't understand what you mean by this ... my source was originally 720x480 and definitely 4:3, it is from 1980s video footage. i don't know how they were encoded to 720x480 mov or avi files, but if it is a square v rectangular pixel issue, is there a way for me to compensate with this in the ffmpegx settings ?

i've seen encoded files from the same set in dvd studio pro and they came out fine & full screen 4:3.

thanks,

mark

[Case]

is there a way for me to compensate with this in the ffmpegx settings ?

Yes: make sure letterboxing is off. Then the encoded video be "stretched" (back) to full frame.