$ ffmpeg -i s001.m2ts -r 30000/1001 -acodec pcm_s16le -vcodec mjpeg \ -interlace 0 -deinterlace -s 720x480 -aspect 3:2 -y s001.movThe version of ffmpeg used here includes patches for the -interlace 0 flag. These patches are available from DVD compliant mpeg2 on Linux. If you perfer not to compile ffmpeg yourself omit the -interlace 0 flag from the above command.
Note the display aspect of -aspect 3:2 is wrong but necessary because Cinelerra requires the pixel aspect ratio to be square to read the file. The display aspect ratio that Cinelerra actually uses for editing is defined explicity in format preferences under settings.
Load the proxy files into Cinelerra's timeline and edit. Smart render jpeg Quicktime to create standard definition previews of your work. If desired, convert the Quicktime output to DVD compliant mpeg2 and create a standard definition DVD. When you are done save the editing project and quit Cinelerra.
$ ffmpeg -i s001.m2ts -r 30000/1001 -acodec mp2 -vcodec mpeg2video \ -interlace 1 -top 1 -flags +ildct+ilme \ -ab 384k -b 24000k -f mpegts -y s001.m2t $ mpeg3toc s001.m2t s001.tocIncrease the bitrate to -ab 448k -b 34000k or greater for better quality.
Again the -interlace 1 and -top 1 flags are only available using the patched version of ffmpeg available from DVD complaint mpeg2 on Linux. These flags may be omitted with only minor loss in quality.
If Cinelerra could decode AVCHD the same way it can decode HDV source, then a direct AVCHD to h264 transcode would be possible. Rendering the entire project with a multi-pass variable bitrate encoder can create a noticably more efficient video stream than the original AVCHD source. Moreover, it is easier to ensure such an encode will meet the requirements for playback in Blu-ray players.
Kdenlive can decode AVCHD and renders h264 using libx264 through ffmpeg. However, the resulting video stream may not include nal hrd packets. I've heard tsmuxer creates them when multiplexing blu-ray, but I see no way to specify the field order. The only alternative seems to be rendering to an intermediate format and then reencoding with x264 for burning to a BD5 or BD9 disk.
The current workflow transcodes the AVCHD source twice. The main drawback of this workflow is the additional time necessary to create the intermediate format. If quality is impacted increase the bitrate for the intermediate format to 34000k or more.