Maintaining quality from Flip Video to DVD

[mk4kc5cmc4@gmail.com]

Hello all,

Newb to video recording here, but very experienced with all forms of audio.....

I've filmed a couple of concerts now using a Flip Ultra HD camcorder, which records with the following details:


* Resolution: HD 720p (1280x720, 16:9 widescreen) at 30 fps (constant frame-rate), progressive scan
* Format: H.264 video compression, AAC audio compression, MP4 file format


I have a high quality audio recording of the concerts that I used to replace the camera's audio. My audio editing software (Ableton Live) happens to handle the Flip video, so I was able to successfully sync the new audio to the video. I exported the new files as .mov's, 1280x720 16:9, with 'current' as the setting for frames per second, and all quality sliders set to 'Best'.

As expected, the files took AGES to render (~27 hours for 40 minutes of video), and the resulting files are HUGE. The original file is 3.28 gigs, and the rendered file with the new audio is like double the size, 7.2 gigs.

I used DVD Flick to author a DVD, and everything worked great, but I did detect a *slight* quality loss with DVD Flick having to squeeze ~14 gigs onto a 4.7gig DVD.

So I have a couple question:

1) Am I rendering properly? The rendered files look great, but they are SO much bigger than the originals, which obviously have the same quality. The audio I added to them is not that big (~400meg for each video file), so why are the rendered files so huge?

2) Ableton is an audio editor that happens to handle some video formats - I used it because I own it & know it. Would I gain anything (specifically in rendering times) by using something like Sony Vegas? I don't need to do anything to the videos other than replace the audio>author DVD>burn.


3) Should I render to h.264 instead of .mov?

4) Should I render at 30fps or automatic?


Thanks everyone......this site has been invaluable to me.

[Supreme2k]

.mov is simply a container, but usually carrying Apple formats.

Use avidemux.

Open the file, select Audio from the top menu, then Main Track, choose external sound file. Make sure that the video is set to Copy and the Audio is set to AAC or WAV, Format is MP4, click save (diskette button). It should take from a few seconds to maybe a few minutes (probably well under 10).

[mk4kc5cmc4@gmail.com]

.mov is simply a container, but usually carrying Apple formats.

Use avidemux.

Open the file, select Audio from the top menu, then Main Track, choose external sound file. Make sure that the video is set to Copy and the Audio is set to AAC or WAV, Format is MP4, click save (diskette button). It should take from a few seconds to maybe a few minutes (probably well under 10).

Use it to render? And it will render that much video in under 10 minutes?


Will I be able to sync the new audio to the video in Avidemux? The audio & video are not the same length, I need to line up the audio file with the video file.

[guns1inger]

A couple of things to understand :

1. Every time you re-encode video using lossy codecs you lose some quality. This is unavoidable. Good encoding may at least keep the quality drop from being noticeable.

2. If you are only changing the audio, and not editing the video, you should export the audio only, and re-sync with the original video. This avoids a needless re-encode of the video. In the case of your audio editor, it may that is is encoding the video without compression, which will preserve the quality, but give you huge files.

3. Your Flip records at 720p (1280 x 720). DVD has a maximum resolution of 720 x 480 (576 in PAL land), so you are going to take a noticeable hit when you encode for DVD. Again, this is unavoidable.

4. 14 GB onto a DVD means nothing. What is the running time ? File size = running time X bitrate. The more you try to put on the DVD (length wise), the smaller the bitrate and the more quality will be affected.

[mk4kc5cmc4@gmail.com]

OK, let's see:


>1. Every time you re-encode video using lossy codecs you lose some quality. This is unavoidable. Good encoding may at least keep the quality drop from being noticeable.



Yes, very familiar with this concept from the world of audio. Can't go wav>mp3>wav without a loss of quality. Of course, with audio I know that I can convert a wav to a 320kbps mp3 with almost no quality loss, and a HUGE savings in file size. I'm looking for the rough video equivalent for that. 90% of the quality in 10% of the size. It may not be possible.


>2. If you are only changing the audio, and not editing the video, you should export the audio only, and re-sync with the original video. This avoids a needless re-encode of the video. In the case of your audio editor, it may that is is encoding the video without compression, which will preserve the quality, but give you huge files.



OK, that makes sense. How would I sync the audio to the video though? Avidemux & just select the rendered audio file as the audio track? Any idea on what I can expect as far as rendering times per hour of video?


>3. Your Flip records at 720p (1280 x 720). DVD has a maximum resolution of 720 x 480 (576 in PAL land), so you are going to take a noticeable hit when you encode for DVD. Again, this is unavoidable.


OK, thanks for the info. This makes me think that what I have now is just about the best I can get, as a visual inspection of the final DVD vs the rendered video files with the new audio is pretty damn close. A little loss of quality, but certainly watch-able. I just wanted to make sure I wasn't missing any glaringly obvious ways to preserve quality.

Sub-questions:

1) Would getting a dual layer burner help this at all?

2) Assuming the final delivery method is DVD, would rendering to 720 x 480 be better than rendering to 1280x720?


>4. 14 GB onto a DVD means nothing. What is the running time ? File size = running time X bitrate. The more you try to put on the DVD (length wise), the smaller the bitrate and the more quality will be affected.


Running time for all 4 videos that make up the concert is ~ 2.5 hours. I authored 2 different versions, one was the entire concert, and one was seperate DVD's for set 1 & set 2 of the show. There was a noticeable increase in quality splitting the concert into 2 discs.

Thanks again for all the help!

[guns1inger]

Yes, going dual layer will help in this case.

Syncing the new audio should not be difficult, and could be done when authoring, depending on your process.

While it is possible to get good quality at much smaller file sizes, you have the added complication of wanting a DVD Video as output. This means certain criteria must be met (mpeg-2 encoding for video etc) which means you wont be able to get the same compression that H264 would provide, for example.

If it were me doing this, I would;

1. Edit the audio and output as AC3 from my editor. I don't know if Ableton Live has AC3 output capabilities. If it does not, output an uncompressed PCM wav instead.

2. Encode the video as an elementary stream based on dual layer capacity. If you go dual layer then you have the opportunity to keep the uncompressed audio and not have to encode it as AC3, if you prefer.

3. My preference for easy encoding is AVStoDVD. It uses HCEnc for video encoding, which gives good quality. You can also load your original Flip video, remove the audio track (right-click menu) and add a new audio track. You can also have AVStoDVD create either an authored disc ready to burn, or output elementary streams encoded and ready for authoring in an external program.

4. Author the streams using my authoring program of choice (I use DVD Lab Pro, but anything you are happy with is fine at this stage)