ReplayTV 4000 Series

For MPEG-2 usage with the 5000 series, visit the ReplayTV5KMPEG-2Usage section.

Quick Reference

QualitySetting	Resolution	Video Bitrate	Audio Bitrate
High	720x480 (D1)	6Mbps VBR	128 or 224 kbps
Medium	720x480 (D1)	4Mbps VBR	128 or 224 kbps
Standard/Extended	352x480 (HHR)	2MBps VBR	128 or 224 kbps

Although the streams are all VBR (Variable Bitrate) the MPEG header shows a constant or nominal bitrate. It should also be noted that High can peak at 12Mbps which is incompatible with DVD specifications which max at 9.7Mbps.

Technical Profile

Parameter	Setting
System Stream Type	Program
Video Standard	NTSC
Video Compression	MPEG-2
Video Bitrates	(see above)
Resolution	(see above)
Frame Rate	29.97 fps
Drop Frame Flag	Not Set
Constrained	No
IQ Matrix	False
Non-IQ Matrix	False
Aspect Ratio (Standard)	4:3 (640x480)
Aspect Ratio (High/Medium)	4:3 (720x540)
Sequence Format	Interlaced
Field Order	A (top first)
Chroma Format	4:2:0
Profile/Level	MP@ML
Color Primaries	ITU-R BT.470-2 System B, G
Transfer	ITU-R BT.470-2 System B, G
Matrix	FCC
Quantizer Scanning Pattern	zigzag
Quantizer Scale	1
Intra DC Precision	8
Intra VLC Format	1
Audio Compression	MPEG-1 Layer 2
Audio Stream	Stereo, 48kHz
Audio Bitrates	(see above)
Frame Length	24.0 ms (384 bytes if 128kbps or 672 bytes if 224kbps)
VBV Buffer	112 / 224
VBV Delay	65535
Minimum Buffer Size	229376 bytes

MUX Rates

All measurements are bits per second

QualitySetting	System	Video	Audio
Standard	1948000	1820000	128000 or 224000
Medium	4224000	4000000	128000 or 224000
High	6224000	6000000	128000 or 224000

Notes and Issues

System Stream

Video Stream

Video Stream Packet Length usually around 2054 bytes.

Audio Stream

It is not yet known what causes the audio bitrate to be 128 on some recordings and 224 on others.

-- LeeThompson - 20 Apr 2002

I know that a number of people have looked at playing back non-Replay generated MPEG files (after generating a ndx file using your utility) with little/no success. Do you guys have any notes on what has been tried, what results have been seen, and any theories you have on why it doesn't work? It seems like a fun problem to look into...

Is there any reason to believe that, once it is determined why non-Replay generated MPEGs don't play back, we couldn't write a utility to do a transform to make an MPEG compliant? Do you think the problem is in the MPEG format itself, perhaps requiring a complete re-encoding with a encoder that emits something Replay's MPEG chip will accept (ugh), or do you think that some unused area in the MPEG format is being used to store checksum/CRC data either by the encoder chip or by the Replay itself?

--Joe

-- JoeToomey - 10 Jan 2003

Topic ReplayTVMPEG-2Usage . { Edit | Attach | Ref-By | Printable | Diffs | r1.14 | > | r1.13 | > | r1.12 | More }

Revision r1.14 - 01 Apr 2003 - 04:22 GMT - TWikiGuest Parents: GuideSnapshot > ReplayShow > GOP > MPEG-2	Copyright © 2001 by the contributing authors. All material on this collaboration tool is the property of the contributing authors. Ideas, requests, problems regarding TWiki? Send feedback.

	Replay	ReplayTVMPEG-2Usage
	Home \| Changes \| Index \| Search \| Go