Which AVC/H264 Encoder Supports Interlced PiCAFF and MBAFF?

[Bonie81]

Which AVC/H264 Encoder Supports Interlaced PiCAFF and MBAFF?

Following is the excerpts from AfterDawn.

Picture-Level Frame/Field Coding

PicAFF, or Picture-adaptive Frame-Field Encoding, is an advanced video encoding technique used in MPEG-4 AVC. Maintaining the quality of interlaced video can be a challenge in video encoding because of the larger spaces between horizontal lines in the same field. While MPEG-1 doesn't support interlaced video at all and MPEG-2 requires entire streams (files) to be either interlaced or progressive, AVC allows individual frames, or even macroblocks to be encoded as interlaced or progressive, depending on whether there are significant differences between the top and bottom fields.

In addition to quality improvements, progressive frames require fewer bits making them more compressible for the same quality as interlaced frames. Just as high quality deinterlacers first look to see if there's motion from one field to another within the same frame, when using PicAFF encoding an AVC encoder looks for motion to determine whether both fields shold be encoded as a single progressive frame or separate interlaced fields. While not as efficient as the alternative, MBAFF, in terms of file size, it results in faster encoding and is supported by more AVC decoding software.

Macroblock-Adaptive Frame/Field Coding

MBAFF, or Macroblock-Adaptive Frame/Field Coding, is a video encoding feature of MPEG-4 AVC that allows a single frame to be encoded partly progressive and partly interlaced. Maintaining the quality of interlaced video can be a challenge in video encoding because of the larger spaces between horizontal lines in the same field. MBAFF allows an AVC encoder to examine each block in a frame to look for similarities between interlaced fields. When there is no motion the fields will tend to be very similar, resulting in better quality if you encode the block as progressive video. For blocks where there is motion from one field to another the quality is more likely to suffer if encoded progressive, so these blocks can remain interlaced.

In addition to quality improvements, progressive frames require fewer bits making them more compressible for the same quality as interlaced frames. This also applies to individual macroblocs, meaning that by using MBAFF you may greatly improve quality for a given bitrate. Since all the decisions required for MBAFF are made by the encoder it can slow encoding speeds greatly. Being a relatively new technology it's also not supported well among AVC playback software. Unlike many of AVC's advance features, though, MBAFF doesn't affect decoder speed.

Definitely, both, result-in better Quality Video Output.

[poisondeathray]

x264 supports MBAFF only, but the adaptive aspect hasn't been implemented yet

mainconcept avc can use either MBAFF or PAFF , but certain versions have restrictions (you need the more expensive versions or SDK to have more features enabled)

[Bonie81]

@poisondeathray

Thanks for looking and your response.
What are the command-line options for MBAFF with x264?

[poisondeathray]

You add --tff or --bff (top field first or bottom field first)

[Bonie81]

@poisondeathray

Tks
i will try on interlaced samples and see.

[Bonie81]

if x264 fully supports MBAFF, the options should be like --mbaff-tff or --mbaff-bff. LOL.