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WSC4
13th June 2019, 03:14
I have read when AVCHD is recorded on a DVD, the disc's maximum spin speed limits the data rate to 18Mb/s. However, this info was printed circa 2009.

http://www.avchd-info.org/format/index.html

https://vision.unipv.it/mst/mat/Sony_AVCHD.pdf <== AVCHD Specifications on page 7.

My Panasonic video camera records AVCHD into a BDMV folder and to this format:

Format: AVC
Format/Info: Advanced Video Codec
Format profile: High@L4.2
Format settings: CABAC / 2 Ref Frames
Bit rate mode: Variable
Bit rate: 23.8 Mb/s
Maximum bit rate: 25.0 Mb/s
Width: 1920 pixels
Height: 1080 pixels
Frame rate: 50.000 FPS
Colour space: YUV
Chroma subsampling: 4:2:0
Bit depth: 8 bits
Scan type: Progressive

Maximum Overall bit rate with audio: 28.0 Mb/s

My Pioneer Blu-ray player is about 5 years old, and I burnt the BDMV folder to a DVD and the Pioneer played it with no problems.

My question is, have they changed the AVCHD specifications in this day and age. Are later Blu-ray player able to read a DVD faster? How far can I push the maximum Overall bit rate?

Sharc
13th June 2019, 07:43
I don't think that the specs have changed. AVCHD on DVD medium is a subset of the broader AVCHD standard. Your blu-ray player probably complies with the full AVCHD standard (check the datasheet), however there is no warranty for playing DVD discs (4.7 or 9 GB) with AVCHD material which exceeds the "AVCHD on DVD media" specs. It may work in your case but it may fail in other cases (other DVD brand, other player). It's probably safer to burn your AVCHD material on BD25 discs. That's how I see it.

Ghitulescu
14th June 2019, 10:31
It's not what AVCHD requires, but what the drive reading DVDs can.

Double standard drives (BD+DVD) can read higher bitrates from the same DVD than pure DVD drives, for they have been designed for a max. 18Mbps (double the DVD specs). BTW, these are the specs for pressed media, not for recordable ones, since the bitrate reqs for the latter are lower. Double sided recordables should consider a further reducing of the bitrate.

Now, that BDRs are so cheap and DVDRs with AVCHD pose some issues with some players, why insisting on BD5/BD9?

frank
20th June 2019, 08:59
Look at DOOM9 Encoding Video for Blu-Ray using H264/AVC (https://forum.doom9.org/showthread.php?t=154533)
For AVCHD you can use 15MB/s and GOP 48. Works on DVD.

Sharc
20th June 2019, 13:29
15MB/s apply for the video alone. Video + Audio + subs can be up to 18MB/s, limited by the classic DVD drives, I understand.

WSC4
24th June 2019, 04:11
Thanks for your info on this and I read the Encoding Video for Blu-Ray using H264/AVC link with interest.

The Blu-ray player I got was their flagship model back then and was expensive. It may have smarts built in with a better read speed and buffers / cache et cetera of some sort. I was going to test its limit by burning several AVCHD DVDs to an Overall bit rate of 30, 32, 34 and 36 Mb/s, but I decided I could not see the point.

The DVDs I burn have only 8 short films, and each film is 3 to 4 minuets long with a total time of approximately 30 minutes and almost fills the DVD-5 disc. These I send to family, friends and others et cetera. Their Blu-ray players could be dated new or old and I know a few are dated 2012.

I am not using the AVCHD format with .m2ts files any more and have changed to the Matroska container. I burn the DVDs as data discs. They don't have menus and chapters and the videos play sequentially. Because of the older players, I will never encode over 18 Mb/s - video including audio.