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DVD Architect imported mpeg2 videos bigger than expected
Hi,
I’m trying to fit 24 videos (4h 43m in total) on one 4,7 DVD disc. Initially they were MP4 files. I did “Optimize Disc” to get the default bitrate of 1,700 Mbps. Everything seemed fine. The Disc Space Used Indicator was yellow meaning that the content would fit. I proceeded to Make DVD. Clicked on Prepare and the compressing process started. Since the whole thing was estimated to take a long time and I didn’t know if the quality of the videos would be satisfactory to me I decided to cancel the process and compress the videos myself with an external program and then import them into DVDA. I tried “Total Video Converter” and also “Any Video Converter” for this purpose. I set up all necessary parameters: video bitrate 1,700, ratio 4/3, video resolution 720×576 PAL, audio ac3 192kbps. Total size was 4,047 GB. However, as I imported them into DVDA the Disc Space Used Indicator was red showing a total of 4,8GB !!! Moreover, audio in some of the videos was “not compliant with the disc format” and was to be recompressed although I compressed all of them mp4 files with the same parameters. Could somebody please tell me what is going on here? How do I solve this problem?
Btw… according to this DVD calculator the bitrate could be even 1,900:
https://dvd-hq.info/bitrate_calculator.php?length=283&vformat=PAL&audiobr=192&astreams=1&ratemode=CBR&motion=Heavy&scenedetect=Active&brlimit=9800&discsize=4482&otherassets=1#CalculatorWhat do you think of all that?
Thanks.
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4 Replies
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Calculating bit rate is an imprecise science because the calculators can only estimate the final file size. The amount of compression depends on too many variables to be calculable to an exact value.
4 hours of edited MP4 source recompressed to a DVD-5 is going to look like…..
But, you might try using dvdshrink: https://www.dvdshrink.org/.
Steve Mann
MannMade Digital Video
http://www.mmdv.com -
Thanks for the response.
I still would like know why DVDA miscalculates the final size of data. I’m saying this because yesterday I tried another utility for DVD authoring called TMPGEnc Authoring Works 4 and I did manage to jam in all of the videos. The space they took was as expected, give or take a few MB, with 400MB left unused. So the bitrate calculator was very accurate. Take a look:
https://dvd-hq.info/bitrate_calculator.php?length=283&vformat=PAL&audiobr=192&astreams=1&ratemode=CBR&motion=Heavy&scenedetect=Active&brlimit=9800&discsize=4482&otherassets=400#Calculator -
As I said, there’s too many variables for *any* program to accurately predetermine file size. DVDA just happens to be more conservative than most. If your video has a lot of motion between i-frames, then there’s more data that the encoder has to account for than if there are few changes from i-frame to the next i-frame. Even the parameters that you give the encoder will affect the encoded file size. And that’s just the main media. Add to that motion menus, static menus? text-only menus? how many? transition menus? extras file? stop page? second audio track? subtitles? All of these are in the final disc image, and there is simply NO way that a bit-rate calculator can account for all of these variables without actually encoding the file.
That is why it’s called an estimate.
Steve Mann
MannMade Digital Video
http://www.mmdv.com -
DVDA has a very long history of incorrectly reporting file sizes.
That’s why I use the bitrate calculator at https://www.johncline.com/bitcalc110.zip.
The only changes I make are to change the default Safety number from 1% to 5% and click the “1 Kilobit = 1000 bits” option found in the settings window.
I’ve been using this for several years now and it’s never let me down.
If DVDA ever says the file is too large, I ignore the warning and it doesn’t put up any kind of fuss 🙂
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