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Hi, dgcom!
Five months ago I have asked Ligos support to do something with field order. They answered that they know this problem and will correct it in ... 2-3 months. Well, we have some time before next millenium
The technique you decribed works, but it involves one recompression step. If you make vbr mpeg2 from original movie and from new one, with reversed field order, the datarate of "corrected movie" will be higher, thus indicating that DV recompression is not perfect process. It also takes time and disk space.
If you make uncompressed RGB24 movie, you'll get original datarate from mpeg video after compression.
However, if you set the same encoding parameters, but force lsx to make mpeg1 file, you will get same datate and quality as in the case of mpeg2 (actually the encoding settings are common for both formats), but correct field order!
Such movie is played well in software, and with hardware decoder like Hollywood+. You have to use single B frame between I or P frames to escape hardware decoder picture distortions with mpeg1. By all other features the picture is very good.
I also found that Panasonic encoder with turned off prefiltering gives better quality than even lsx with vbr.
So, I do not see any reason to tie myself to mpeg2, until there would be definitely mpeg2 encoder, but not their mpeg1-based imitations, like lsx encoder.
Of course, I can multiplex mpeg1 video into mpeg2 stream and get "valid mpeg2", which now takes much more CPU power and requires third-party decoder
.
But what is the reason to do this?
As for deinterlacing, this is the only way to make acceptable movie for PC screen. Another way is to extract fields, create 50 fps movie and compress it into mpeg. It is possible with Premiere to write transition factory transition and produce 1/2 speed movie that contains all fields resized to full height. Then, use VirtualDub to change fps to 50 (or 60 for NTSC). Then you compress the movie into mpeg and get smooth motion video. The drawback is that you loose half of vertical resolution for still pictures.
50 FPS D1 size mpeg movies can be played on 500 MHz PC. They really preserve the smooth motion of original video. However, the datarate must be doubled for them.
Caution: not every third-party Premiere plugin can work with fields. Some of them just apply transitions to one half of frame, and leave another half black. Another may simply crash. The example is huge memory leak in lense flare filter of Premiere 4.2, when it is used in field rendering.
Grigory
Five months ago I have asked Ligos support to do something with field order. They answered that they know this problem and will correct it in ... 2-3 months. Well, we have some time before next millenium
The technique you decribed works, but it involves one recompression step. If you make vbr mpeg2 from original movie and from new one, with reversed field order, the datarate of "corrected movie" will be higher, thus indicating that DV recompression is not perfect process. It also takes time and disk space.
If you make uncompressed RGB24 movie, you'll get original datarate from mpeg video after compression.
However, if you set the same encoding parameters, but force lsx to make mpeg1 file, you will get same datate and quality as in the case of mpeg2 (actually the encoding settings are common for both formats), but correct field order!
Such movie is played well in software, and with hardware decoder like Hollywood+. You have to use single B frame between I or P frames to escape hardware decoder picture distortions with mpeg1. By all other features the picture is very good.
I also found that Panasonic encoder with turned off prefiltering gives better quality than even lsx with vbr.
So, I do not see any reason to tie myself to mpeg2, until there would be definitely mpeg2 encoder, but not their mpeg1-based imitations, like lsx encoder.
Of course, I can multiplex mpeg1 video into mpeg2 stream and get "valid mpeg2", which now takes much more CPU power and requires third-party decoder
. But what is the reason to do this?
As for deinterlacing, this is the only way to make acceptable movie for PC screen. Another way is to extract fields, create 50 fps movie and compress it into mpeg. It is possible with Premiere to write transition factory transition and produce 1/2 speed movie that contains all fields resized to full height. Then, use VirtualDub to change fps to 50 (or 60 for NTSC). Then you compress the movie into mpeg and get smooth motion video. The drawback is that you loose half of vertical resolution for still pictures.
50 FPS D1 size mpeg movies can be played on 500 MHz PC. They really preserve the smooth motion of original video. However, the datarate must be doubled for them.
Caution: not every third-party Premiere plugin can work with fields. Some of them just apply transitions to one half of frame, and leave another half black. Another may simply crash. The example is huge memory leak in lense flare filter of Premiere 4.2, when it is used in field rendering.
Grigory
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