[Cin] HDV on a Blu-ray Disc Without Re-encoding

Mon Nov 23 02:20:30 CET 2020

В сообщении от Monday 23 November 2020 03:51:36 Terje J. Hanssen via Cin написал(а):
> This topic is treated with reference to the current  Cinelerra-GG Manual 
> (and in the Features5 document at least since early 2018):
> 
>   * 14.6 HDV on a Blu-ray Disc Without Re-encoding
> 
>     An MTS file is a video file saved in the high-definition (HD) MPEG
>     Transport Stream video format, commonly called AVCHD. It contains HD
>     video compatible with Blu-ray disc format and is based on the MPEG-2
>     transport stream. MTS files are often used by Sony, Panasonic, Canon
>     and other HD camcorders. Legal in-
>     put for Video – MPEG1VIDEO, MPEG2VIDEO, H264; Audio – MP1, MP2, AC3,
>     AC3PLUS, DTS, TRUHD.
> 
>     For creating a blu-ray disc, if you have HDV MPEG-2 media that is in
>     blu-ray format, you can save the original quality of your work,
>     rather than rendering it to another format. Follow the steps below
>     directly instead of going through C INELERRA-GG. It has been tested
>     on 10 different MTS files.
> 
>     du -sb /yourHDVfile.MTS     # Determine the size of your file in bytes.
> 
>     blocks=((size-in-bytes/2048 + 4096))     # Convert bytes into blocks
>     + a little more.
> 
>     mkudffs /tmp/newfilename.udfs blocks     # Create a file with that #
>     of blocks + some extra.
> 
>     mount -o loop /tmp/newfilename.udfs /mntX     # Use a mount point
>     like mntX that is not in use.
> 
>     /<cinelerra_installed_path>/bin/bdwrite /mntX /tmp/yourHDVfile.MTS
>          # Substitute cinelerra path.
> 
>     umount /mntX    # You must unmount the udfs filesystem
> 
>     growisofs -Z /dev/bd=/tmp/newfilename.udfs     # Replace /dev/bd
>     with your bluray hardware device.
> 
>     OR dd if=/tmp/newfilename.udfs of=/dev/bd bs=2048000     # if using
>     rewritable blu-ray; replace bd.
> 
> ===================
> 
> When the 1080i/25 HDV-source is recorded via i.Link (Firewire) to disk, 
> the file type and format is HDV.M2T
> 
> For this test I use the same, downloaded HDV file as previous mentioned 
> (not my file or camcorded by me!)
> 
>      Stream #0:0[0x810]: Video: mpeg2video (Main) ([2][0][0][0] / 
> 0x0002), yuv420p(tv, bt709, top first), 1440x1080 [SAR 4:3 DAR 16:9], 
> 25000 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc
>      Stream #0:1[0x814]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, 
> stereo, s16p, 384 kb/s
> 
> 
> The MPEG2 Video stream is Blu-ray compatible format, while the MP2 Audio 
> stream has to be converted to AC3.
> 
> Demux, convert the audio and remux to a M2TS stream using this ffmpeg 
> command:
> 
> ffmpeg -i 20081103140154.m2t -vcodec copy -acodec ac3 20081103140154.m2ts
> 
> ............. skip
> 
> Input #0, mpegts, from '20081103140154.m2t':
>    Duration: 00:00:13.44, start: 1042.400000, bitrate: 26598 kb/s
>    Program 100
>      Stream #0:0[0x810]: Video: mpeg2video (Main) ([2][0][0][0] / 
> 0x0002), yuv420p(tv, bt709, top first), 1440x1080 [SAR 4:3 DAR 16:9], 
> 25000 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc
>      Stream #0:1[0x814]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, 
> stereo, s16p, 384 kb/s
>      Stream #0:2[0x815]: Unknown: none ([160][0][0][0] / 0x00A0)
>      Stream #0:3[0x811]: Unknown: none ([161][0][0][0] / 0x00A1)
> Stream mapping:
>    Stream #0:0 -> #0:0 (copy)
>    Stream #0:1 -> #0:1 (mp2 (native) -> ac3 (native))
> Press [q] to stop, [?] for help
> Output #0, mpegts, to '20081103140154.m2ts':
>    Metadata:
>      encoder         : Lavf57.83.100
>      Stream #0:0: Video: mpeg2video (Main) ([2][0][0][0] / 0x0002), 
> yuv420p(tv, bt709, top first), 1440x1080 [SAR 4:3 DAR 16:9], q=2-31, 
> 25000 kb/s, 25 fps, 25 tbr, 90k tbn, 90k tbc
>      Stream #0:1: Audio: ac3, 48000 Hz, stereo, fltp, 192 kb/s
>      Metadata:
>        encoder         : Lavc57.107.100 ac3
> frame=  336 fps=0.0 q=-1.0 Lsize=   45549kB time=00:00:13.43 
> bitrate=27774.3kbits/s speed= 107x
> video:41008kB audio:315kB subtitle:0kB other streams:0kB global 
> headers:0kB muxing overhead: 10.225909%
> 
> Comment
> The default AC3 bitrate 192 kb/s here is halph of the source MP2 bitrate 
> 384 kb/s. Any idea about the quality difference?

Try to listen to it (with VLC?)? 

*I think* 384 kb/s was for 5.1 ac3 sound ..
so, stereo can be compressed further.

https://www.vegascreativesoftware.info/us/forum/ac-3-bitrate--63214/
this says 448 kb/s for 5.1

> 
> ================
> 
> So further to trouble using the procedure steps from the Manual above:
> 
> Determine the size of the file in bytes.
> 
>     du -sb 20081103140154.m2ts
>     46642368    20081103140154.m2ts
> 
> 
> Try to calculate the blocks as
> 
>     blocks=((/466423682048 + 4096)) = 26870.59375 ??
> 
> 
>     # mkudffs /tmp/bd_20201122_hdv_m2ts.udfs blocks 26870.59375
>     mkudffs: invalid block-count
> 
> 
> Obviously something went wrong here.

Try to round up this size in blocks?
 26870.59375 -> 26871

> 
> Could someone test and verify these steps and further, to see if a 
> successful Blu-ray BDAV structure is created?
> 
> (Just now I have no Blu-ray burner in my working PC, so I have to wait 
> with burning the image to a BD-R/RE discs).
> 
> ------------------
> 
> Terje J. H
> 
> 
> One current and one previous related Blu-ray mail threads as references:
> https://lists.cinelerra-gg.org/pipermail/cin/2020-November/002709.html
> https://lists.cinelerra-cv.org/pipermail/cinelerra/2016q4/005609.html
> 
> 
> 
> 