DV on Blu-ray

[Mark Donnell]

This discussion has occurred once before on this forum, but perhaps somebody has new experience. The reality is that DV, played back from tape by the camcorder into a TV, is significantly sharper and better looking than I have ever been able to get by converting to DVD. This makes sense, based on the reduced maximum data rate imposed by the DVD standard. Is it possible to convert DV to MPEG-2, then to record it to Blu-ray and maintain the same quality as the original tape ?

[Perrone Ford]

Answer is probably yes. But why would you convert to Mpeg2 to go to bluray? That seems a very odd choice.

[Wacharapong Chiowanich]

Looks like the OP intends to encode his DV materials to the Blu-ray Video format as opposed to simply recording the DV materials as data in the original format on Blu-ray discs. If this is the case, the DV content has to be encoded to either Mpeg 2, VC-1 or H.264.

To answer the question if the quality can be preserved, I believe it can as the maximum bit rate allowed by the Blu-ray video specs is very high at up to about 40 Mbps for the video stream(s) in any of the above codecs which are more efficient than DV.

[Randall Leong]

Originally Posted by Wacharapong Chiowanich

To answer the question if the quality can be preserved, I believe it can as the maximum bit rate allowed by the Blu-ray video specs is very high at up to about 40 Mbps for the video stream(s) in any of the above codecs which are more efficient than DV.

And the higher bitrates will minimize the quality loss due to re-compression. You see, DV is already compressed (and lossy compression similar to MPEG-2, at that). But the bitrate is high enough on DV (25 Mbps CBR for video) to be visually acceptable.

[Mark Donnell]

Perrone - my intent was to be able to play the DV back on a Blu-ray player, not to store it for future use. At present, to obtain the best picture, I have to play it back through the camcorder to a TV, which is less convenient than using a Blu-ray player. Thanks for all the replies.

[Perrone Ford]

I have not attempted to try to encode SD for BluRay playback. I am not even sure it would work. I think what you'd end up with is either a highly scaled video, or a small DV video in the middle of an HD screen. Not sure I'd care for either of those scenarios.

That said, VC1 or Mpeg4 will fare MUCH better at preserving the original quality of the video than Mpeg-2. That's not a choice I would use.

[Randall Leong]

Originally Posted by Perrone Ford

I have not attempted to try to encode SD for BluRay playback. I am not even sure it would work. I think what you'd end up with is either a highly scaled video, or a small DV video in the middle of an HD screen. Not sure I'd care for either of those scenarios.

That said, VC1 or Mpeg4 will fare MUCH better at preserving the original quality of the video than Mpeg-2. That's not a choice I would use.

Actually, 480i and 576i (the interlaced standard-definition formats) are part of the Blu-ray standard. It's just that very few people choose to master SD video onto Blu-ray Disc for the main video content.

[Perrone Ford]

Originally Posted by Randall Leong

Actually, 480i and 576i (the interlaced standard-definition formats) are part of the Blu-ray standard. It's just that very few people choose to master SD video onto Blu-ray Disc for the main video content.

I just did a preview of this. And as I suspected, it letterboxed the NTSC material to fit onto an HD sized screen. If played back on a SDTV this would probably look ok. If played on an HD screen, it would probably look quite poor.

I don't know what happens when you connect a DV camera to an HD screen. Does it scale the same way?

[Randall Leong]

Originally Posted by Perrone Ford

I just did a preview of this. And as I suspected, it letterboxed the NTSC material to fit onto an HD sized screen. If played back on a SDTV this would probably look ok. If played on an HD screen, it would probably look quite poor.

I don't know what happens when you connect a DV camera to an HD screen. Does it scale the same way?

Actually, 4:3 SD material is stored on disk in its native resolution and aspect ratio. It's the BD player that pillarboxed this material in Blu-ray mode.

If DV is connected to the HDTV set, then it depends on the settings of the HDTV set itself (by default, most HDTV sets stretch 4:3 material to fill the entire screen without any cutoff, resulting in distorted images). The other commonly available settings are "zoom" and "4:3 pillarbox" (or similar).

[Mark Donnell]

When I play a DV tape into my 40" LCD from the camcorder, I use the S-video output from the camera to the S-video input on the TV and adjust the TV picture aspect ratio to 4:3. It produces a very good picture (for DV). I guess I'll just have to do some experimentation, and I'll try the H.264 route as well. Perhaps a better option would be to recode to 720p and then to a Blu-ray format.

[Randall Leong]

Originally Posted by Mark Donnell

When I play a DV tape into my 40" LCD from the camcorder, I use the S-video output from the camera to the S-video input on the TV and adjust the TV picture aspect ratio to 4:3. It produces a very good picture (for DV). I guess I'll just have to do some experimentation, and I'll try the H.264 route as well. Perhaps a better option would be to recode to 720p and then to a Blu-ray format.

This is relatively rare - especially since most people who play back DV tapes directly on an HDTV set use nothing more than the standard composite video connection. The picture quality with this type of connection will be worse than via the S-Video connection - not only because composite video is limited in horizontal resolution to about 360 TV lines per picture height (versus about 420 TV lines per picture height via the S-Video connection), but also because composite video suffers from increased color noise in comparison to even S-Video, let alone component or IEEE 1394a.