Which Format is Better or the Same (MPG vs AVI) when Burned Back to MPEG-2

[victor43]

Hello everyone. Just curious I downloaded a few movies /tv shows and they are in mpg format and some in avi format. I would assume that they are DVD rips files converted into these two different formats. If I want to burn them back to DVD format MPEG-2 which file format contains the best quality when played on a DVD player ? Or would the MPEG-2 quality come out the same ?

Hope the above is clear.

Thanks

[aedipuss]

buy the dvds. downloaded movies/tv shows are illegal warez and not supported here.

[jagabo]

The one that looks better. MPG and AVI may contain low quality or high quality video.

[victor43]

just wanted to know using most dvd ripping software allow you to choose the quality level and also the format to save the decoded video data ? If the software does allow the format which format saves the best quality or is the quality level adjustable ?

[pandy]

If I want to burn them back to DVD format MPEG-2 which file format contains the best quality when played on a DVD player ? Or would the MPEG-2 quality come out the same ?

Usually MPEG-2 (H.262) video can be recorded on DVD-Video without transcoding.
AVI rarely will have H.262 video so transcoding will be required.

[victor43]

If I want to burn them back to DVD format MPEG-2 which file format contains the best quality when played on a DVD player ? Or would the MPEG-2 quality come out the same ?

Usually MPEG-2 (H.262) video can be recorded on DVD-Video without transcoding.
AVI rarely will have H.262 video so transcoding will be required.

Ok then my question with transcoding is there a loss in quality going from MPEG-2 to AVI ?

[videobruger]

is there a loss in quality going from MPEG-2 to AVI ?

This makes no sense. MPEG-2 is a video codec and AVI is a container. In the AVI container there could be a video with MPEG-2 codec as shoen below.

General
Complete name : D:\mpeg2.avi
Format : AVI
Format/Info : Audio Video Interleave
File size : 32.1 MiB
Duration : 56s 720ms
Overall bit rate mode : Variable
Overall bit rate : 4 749 Kbps

Video
ID : 0
Format : MPEG Video
Format version : Version 2
Format profile : Main@Main
Format settings, BVOP : Yes
Format settings, Matrix : Custom
Format settings, GOP : Variable
Format settings, picture structure : Frame
Codec ID : MPEG
Codec ID/Info : Chromatic MPEG 1 Video I Frame
Duration : 56s 720ms
Bit rate mode : Variable
Bit rate : 4 052 Kbps
Maximum bit rate : 9 800 Kbps
Width : 720 pixels
Height : 576 pixels
Display aspect ratio : 16:9
Frame rate : 50.000 fps
Original frame rate : 25.000 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Interlaced
Scan order : Top Field First
Compression mode : Lossy
Bits/(Pixel*Frame) : 0.195
Stream size : 27.4 MiB (85%)

Audio
ID : 1
Format : AC-3
Format/Info : Audio Coding 3
Mode extension : CM (complete main)
Format settings, Endianness : Big
Codec ID : 2000
Duration : 56s 704ms
Bit rate mode : Constant
Bit rate : 640 Kbps
Channel(s) : 6 channels
Channel positions : Front: L C R, Side: L R, LFE
Sampling rate : 48.0 KHz
Frame rate : 31.250 fps (1536 spf)
Bit depth : 16 bits
Compression mode : Lossy
Stream size : 4.33 MiB (13%)
Alignment : Aligned on interleaves
Interleave, duration : 32 ms (1.60 video frames)

[victor43]

is there a loss in quality going from MPEG-2 to AVI ?

This makes no sense. MPEG-2 is a video codec and AVI is a container. In the AVI container there could be a video with MPEG-2 codec as shoen below.

So I understand but does that mean that there would be no loss in quality since AVI is a container for the MPEG-2 encoding ?

[jagabo]

If the DVD MPEG 2 video is simply remuxed into a different container the quality is exactly the same as the source. It's like taking a cake out of one box and putting it into another -- the cake isn't changed. If the video is reencoded the quality will vary depending on the codec and settings used.

So there's no way of predicting the answer to your original question. The AVI and MPG file could both contain the original MPEG 2 video or they could contain high quality reencoded video or crap. The only way to determine which source is better is to view them.

[pandy]

Ok then my question with transcoding is there a loss in quality going from MPEG-2 to AVI ?

Ok, let's try to do pragmatic approach.
MPEG-2 (H.262) is a video codec, MPEG (MPG) is usually container (properly MPEG PS - Program Stream).
AVI is only container so it can be compared to MPEG PS (files with extension .mpg).
MPEG-2 (video codec) can be used with MPEG PS (this is native container for MPEG) or with AVI however usually AVI contain different video codecs than MPEG-2).
Video quality is something not directly related with codecs and containers and at this level of abstraction your question is somehow incorrect.

Question about transcoding - if lossy video codec used as a source to another lossy video coding almost always there is quality loss (exception if some lossless transformation can be performed but this is only theoretical - i'm not aware of existing for this kind of converter but it should be feasible).