Welcome to Doom9's Forum, THE in-place to be for everyone interested in DVD conversion. Before you start posting please read the forum rules. By posting to this forum you agree to abide by the rules. |
|
|
Thread Tools | Search this Thread | Display Modes |
28th September 2019, 19:12 | #1 | Link |
Cary Knoop
Join Date: Feb 2017
Location: Newark CA, USA
Posts: 397
|
Chrominance subsampling for MPEG-2 interlaced encodings
Interlaced MPEG-2 allows the chrominance samples to be aligned temporally to the lines or, less common, to the first field of the frame.
Is there an easy way to determine which method was used during encoding? |
29th September 2019, 02:14 | #2 | Link | |
Registered User
Join Date: Sep 2003
Location: Berlin, Germany
Posts: 3,079
|
Are you referring to field based encoding of interlaced sources? The only encoder which supports this AFAIK is Procoder / Carbon Coder. This option complies with the MPEG2 specs, but not with the DVD specs, so I never used it.
From the ECLPro readme for DVD Rebuilder: Quote:
|
|
12th November 2019, 01:45 | #4 | Link |
Big Bit Savings Now !
Join Date: Feb 2007
Location: close to the wall
Posts: 1,545
|
temporally aligned ? I thought spatially aligned, and both fields coded as one frame,
so chroma will be temporally smeared. Horizontal axis: MPEG-2: aligned on even columns, (col 0,2,4 = even), (MPEG-1: would be aligned in-between neigbored columns 0,1 and 2,3 etc. Vertical axis: MPEG-1 and MPEG-2: aligned midways in-between two lines. http://www.cs.columbia.edu/~delbert/...ranscoding.pdf https://poynton.ca/PDFs/Chroma_subsampling_notation.pdf https://pdfs.semanticscholar.org/9ae...874539ff3d.pdf http://dvd.sourceforge.net/dvdinfo/mpeghdrs.html Extension header. Sequence_Extension Byte5 Bit1, Bit2 chroma_format GoTo H.262 Spec: https://www.google.com/url?sa=t&rct=...A8uq_RQBzRwyCs page 54/220 Table 6-5 chroma_format 00 = Reserved 01 = 4:2:0 10 = 4:2:2 11 = 4:4:4 Ha, found something more: Picture_Coding_Extension Byte7 Bit0 chroma_420_type page 63/220 "chroma_420_type – If chroma_format is "4:2:0", the value of chroma_420_type shall be the same as progressive_frame; else chroma_420_type has no meaning and shall be equal to zero."
__________________
"To bypass shortcuts and find suffering...is called QUALity" (Die toten Augen von Friedrichshain) "Data reduction ? Yep, Sir. We're that issue working on. Synce invntoin uf lingöage..." Last edited by Emulgator; 13th November 2019 at 14:23. |
|
|