Convert .avi files to what???

[hemang]

My Canon digital camera A640 records .avi files, 640x480 pixels, 30fps
Video #0
Codec : M-JPEG
Codec/Info : M-JPEG including Huffman Tables
PlayTime : 29s 966ms
Bit rate : 15 Mbps
Width : 640 pixels
Height : 480 pixels
Aspect ratio : 4/3
Frame rate : 30.000 fps
Resolution : 24 bits
Bits/(Pixel*Frame) : 1.629

Audio #0
Codec : PCM
Codec/Family : PCM
Codec/Info : Microsoft PCM
PlayTime : 29s 967ms
Bit rate : 88 Kbps
Channel(s) : 1 channel
Sampling rate : 11 KHz
Resolution : 8 bits
StreamSize : 322 KiB

The file size is very large, 55Mb.
I want to compress these or convert these to a smaller size, at least 50% less. I have downloaded Super and MediaCoder for this. Super seems good but I am not sure what to convert these into. I had posted this question on MediaCoder forum and got a suggestion that should convert into DVD compatible MPG-2 file. I was not able to do this properly with MediaCoder but managed it with Super. I used MPG-2 container, AC3 for audio, ffmpeg encoder, 720x576 pixels, aspect 4:3, 25 fps, 3024 bitrate, audio 48K freq, channels 2, bitrate 96, for PAL DVD standard. This gives a file of about 12Mb which is ok. But will the quality not deteriorate with the extended pixels (720x576 from 640x480)? Can I burn this MPG-2 file to a DVD and see on TV. I will be deleting the avi file so is this the best approach or should I convert into something else? Please advice

[jagabo]

But will the quality not deteriorate with the extended pixels (720x576 from 640x480)?

Resizing always causes some deterioration (it may not be visible unless you look really closely) but you have no choice if you want DVD compatible MPEG2 files. PAL DVD only supports 720x576, 704x576, 352x576, and 352x288.

Can I burn this MPG-2 file to a DVD and see on TV.

Yes, but you need to use DVD authoring software if you want a DVD that plays on all set-top players. Some players will play "raw" MPG files on data DVDs.

I will be deleting the avi file so is this the best approach or should I convert into something else?

Your bitrate is probably a little low if you want archive quality. Why don't you archive the original file(s) onto a data DVD(s)?

[guns1inger]

NTSC is the closest fit, both in resolution and in framerate. 640 x 480 is in fact NTSC 4:3 with square pixels. Resizing to 720 x 480 will cause minimal distortion, as this happens on playback through your TV direct from the camera anyway. Even resizing for PAL is not a major issue.

The big issue with going to PAL is the framerate conversion. You will lose 5 frames every second, either through blending or dropping. Either way you risk getting a muddy or jerky result. This is minimise by going to NTSC at 29.976 frames per second.

I would convert and author to NTSC if your playback equipment will support it - most PAL equipment does.

[jagabo]

NTSC is the closest fit...

Yeah, I probably should have mentioned that.

[hemang]

Thanks for the replies.

jagabo wrote :
Your bitrate is probably a little low if you want archive quality. Why don't you archive the original file(s) onto a data DVD(s)?


I didn't understand this point. I don't have a DVD writer at present.

Am I right to make MPEG-2 file with the bit rate and resolution I have chosen or should i make a MP4 file or something else. Is there any other way to compress a avi. file??
In India the standard is NTSC but now actually all TV's have noth NTSC and PAL compatibility.
However I presume that since the 640x480 resolution of my avi file is closer to NTSC, I should use NTSC, is this assumption ok? If I keep the fps at 29.976, will it play on my TV. I thought NTSC needed 25 fps?

Are my selections for video and audio settings for the output file ok? Or I need to change them?

[jagabo]

I thought India was a PAL country? In any case, if your equipment plays both you can use either.

NTSC is 29.97 fps. Converting from 29.97 to 25 fps is a bigger problem than resizing the frame. So you will be best off leaving your video at 29.97 fps.

You can create MPEG 2 files with a 640x480 frame. The problem with that is it's not DVD compatible. If you ever want to make regular movie DVDs from your files you'll have to convert them again. Every time you resize digital video, and every time you convert to a lossy codec like MPEG, you will get some degredation in the image quality. If you're eventualy going to make DVDs you're best off doing the conversion to DVD compatible settings in the first place.

MPEG 4 ASP (Divx and Xvid) and MPEG 4 AVC (h.264, x264) have the same issues although they can make your file smaller.

[Midzuki]

You can create MPEG 2 files with a 640x480 frame. The problem with that is it's not DVD compatible.

"DVD-compatible" means DVDForum-compliant, right?

If his SAP supports non-standard resolutions, and if the disk he
wants to create will be viewed at-home only, it wouldn't hurt to try
a 640x480 NTSC DVD.

====================================

[hemang]

Thanks all for the replies. I goofed up a bit. India is a PAL country but the TV's also support NTSC.
So I think I should convet my files to DVD compatible NTSC standard MPEG2 files. I will then delete the avi files, is that ok. If in future I make DVD's they will be for viewing at home only on TV.
So what are the containers I should use for audio and video and the bit rates, frequency etc.
Are MPEG4 files also DVD compatible? Sorry for the silly questions.

[guns1inger]

DVD compliant is mpeg-1 at VCD resolutions, and Mpeg-2 from VCD resolution through to Full-D1 (See What is DVD - top left - corner for details).

Mpeg4 is not DVD compliant.

Most DVD players will also play VCD and SVCD discs (neither of which support resolutions as high as your video).

Some players will happily play mpg files with out authoring, and in a wider range of resolutions than DVD will allow.

Some players will play Divx/Xvid encoded material.

If you want to be able to take your videos with you when you visit relatives, then creating DVD compliant files and authoring to DVD will give you the highest compatibility.

[hemang]

thanks everyone. but you did not not tell me what settings i should use. also, is super a good enough software for this purpose? i need a freeware for this.
Are these settings ok for SUPER:
Output Container : MPEG2, Output video codec : MPEG2, Output Audio codec : AC3
ffmpeg
Video : 720x480, 4:3 aspect, 29.97 fps, 3024 kbps, Hi Quality, 48K Audio
Audio : Sampling freq 48000, Channels 2, 96 kbps

Need this last advice so I can start my work. thanks again to all for replying, really appreciate this.

[jagabo]

You should try for yourself. Take a typical file and convert it using different settings. Compare the results and decide what you're willing to accept.

3024 kbps is probably too low unless your video is from a camera that was mounted on a tripod and there was little motion in the scene. If you were holding the camera by hand, using a lot of zoom, and there's lots of motion, you will probably need twice that to get good results.

The audio bitrate is pretty low too. I'd probably use twice that, 192 kbps. But your source is only 11 KHz so less may be OK.

[Ciffor]

In another forum, you asked me if i would be so nice, as to try to convert avi to mpeg2. My question is: how can it be that you don't try this for your self, as somebody in this thread also mentioned? You would get first hand knowledge about your situation and how to approach it in the future.

[Midzuki]

3024 kbps is probably too low unless your video is from a camera that was mounted on a tripod and there was little motion in the scene. If you were holding the camera by hand, using a lot of zoom, and there's lots of motion, you will probably need twice that to get good results.

According to my own experience, I would recommend 5400kbps to begin with.

=========================================

[hemang]

thanks to all for the replies. i know i will have to finally decied what settings are required but if someone has experience these things then its easier. also i do not have a dvd writer nor a dvd player so i had asked cliffor if he could do this for me. its ok if you cant. i have been able to amke mpeg2 files using super but i cannot write these on dvd and see the results on tv, else i would have done this. anyways thanks all for the help.

[jagabo]

i do not have a dvd writer nor a dvd player so i had asked cliffor if he could do this for me. its ok if you cant. i have been able to amke mpeg2 files using super but i cannot write these on dvd and see the results on tv, else i would have done this.

You don't really need to look at the videos on TV. The problems that arise from too little bitrate are easily visible on a computer. You may have to zoom in to see the artifacts.

The main type of artifact created by MPEG compression is macroblocks. MPEG encoding first breaks the full frame down into 8x8 blocks. It then looks to reduce the amount of information in those blocks to save space. Some details are thrown away. If too much detail is thrown away the resulting frame will have blocky looking artifacts. The loss of detail will make the image look blurry, grainy, or noisy at full speed playback. Here's a 4x enlargment of some DV video and the same video after conversion to MPG at 3000 kbps CBR:





A small amount of macroblocking won't be visible at normal playback speeds. All MPEG encoded video will have a little bit of it, even commercial movie DVDs. Be aware that your MJPEG source probably has a fair amount of it to start with.

[hemang]

thanks again. i will look into the details carefully and take trials with different settings and see whats best for me.