I have been importing both VRO and VOB files from my dvd recorder (Samsung R130) onto the computer using VS10, and then removing commercials from the titles. Before burning to DVD, I save the file keeping most of the setting the same except for the video data rate, and setting the file format to DVD-NTSC. Here’s an example of an input and resulting output properties of one of the titles.
INPUT file properties:
MPEG files
24 bits, 352 x 480, 29.97 fps
Upper Field First
(MPEG-2), 4:3
Video data rate: Variable (Max. 10000 kbps)
Audio data rate: 256 kbps
Dolby Digital Audio, 48 KHz, 2/0(L,R)
File size: 2141760 KB, 7166.700 sec
OUTPUT file properties:
MPEG files
24 bits, 352 x 480, 29.97 fps
Upper Field First
(DVD-NTSC), 4:3
Video data rate: Variable (Max. 6000 kbps)
Audio data rate: 256 kbps
Dolby Digital Audio, 48 KHz, 2/0(L,R)
File size: 4091102 KB, 6359.193 sec
So my first question is why does the file become so inflated although the bitrate setting is actually lower?
Second, I can fit 4 hours in LP mode on the recorder with an apparent Max 10000 kpbs, but of course that is not possible once the files are processed through VS10 – why?
My last question is whether it is better to keep the video bitrate at constant 6000 kbps as opposed to variable for sports (fast action titles). I have noticed some blotchiness in some scenes especially if the camera angles change quickly.
Thanks,
KO
Why are my output mpeg2 files so much bigger than the input?
Moderator: Ken Berry
NNNNNAAAAHHH.... something here isn't making sense. There has to be a mistake with the bit rate or the resolution.... If you are coming close to filling a disk at 6000K then it sounds like the resolution is set at 720x480.
Download a program called VIDEOINSPECTOR (last time I checked, it was free from http://www.videohelp.com ) and confirm all of the bitrates and resolutions are as you have them listed.
Download a program called VIDEOINSPECTOR (last time I checked, it was free from http://www.videohelp.com ) and confirm all of the bitrates and resolutions are as you have them listed.
The reason why it's growing is because the bitrate you see in your input file is not the true bitrate. It's stamped in there by your recorder, but the actual average bitrate is much closer to about 2000kbps to 2500kbps (~2105kbps based on your time and filesize).
Then when you re-encode, you are using a much higher bitrate, and even though you cut some time off, the new file is much larger because you are using 2x-3x the bitrate of the original file.
NOTE: Filesize is mostly based on Video DURATION multiply by video bitrates (either Average Bitrate for VBR encoding, or Actual Bitrate for CBR encoding), as well as the audio type/bitrate. Video effects and/or Resolution will not change the filesize given the same Video Duration and when using the same CBR or same Avg VBR (but using a lower resolution in conjunction with lower bitrates might make the resulting mpeg look better). That is why in LP mode your recorder appears to have dropped to Half D1 resolution.
Regards,
George
Then when you re-encode, you are using a much higher bitrate, and even though you cut some time off, the new file is much larger because you are using 2x-3x the bitrate of the original file.
NOTE: Filesize is mostly based on Video DURATION multiply by video bitrates (either Average Bitrate for VBR encoding, or Actual Bitrate for CBR encoding), as well as the audio type/bitrate. Video effects and/or Resolution will not change the filesize given the same Video Duration and when using the same CBR or same Avg VBR (but using a lower resolution in conjunction with lower bitrates might make the resulting mpeg look better). That is why in LP mode your recorder appears to have dropped to Half D1 resolution.
Regards,
George
NNNNAAAHHHH... still isn't making sense... His output file is TWICE as big as his input file. Adding transitions and such does not account for that kind of file growth.
And yes... there is always a small difference in the SET bitrate and the ACTUAL, but not enough to account for that kind of difference.
He/she is either rendering at a MUCH higher bit rate then needs to be (no sense in rendering at a higher bitrate then the input file) or he/she has made a mistake and rendered at double the resolution (720x480)
Byt the way... you have your resolution posted as 352x480..... are you sure you do not mean 720x480 or 352x240.
The reason that i ask simply is that 352x480 is kind of an oddball resolution. (isn't really used as much as the others)
Again... download VIDEOINSPECTOR... it will tell you the exact bitrates, and resolutions of both files.
And yes... there is always a small difference in the SET bitrate and the ACTUAL, but not enough to account for that kind of difference.
He/she is either rendering at a MUCH higher bit rate then needs to be (no sense in rendering at a higher bitrate then the input file) or he/she has made a mistake and rendered at double the resolution (720x480)
Byt the way... you have your resolution posted as 352x480..... are you sure you do not mean 720x480 or 352x240.
The reason that i ask simply is that 352x480 is kind of an oddball resolution. (isn't really used as much as the others)
Again... download VIDEOINSPECTOR... it will tell you the exact bitrates, and resolutions of both files.
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sjj1805
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The clue is in the word VARIABLE bit rate. If it was CONSTANT bit rate things would be pretty much the same between the original and the new.
The fact you are using VARIABLE tends to suggest that the bit rates have been CALCULATED differently by the encoders.
CONSTANT is better than VARIABLE. Use variable when you are having problems squeezing it all onto a DVD and need to make the file size a bit smaller.
The fact you are using VARIABLE tends to suggest that the bit rates have been CALCULATED differently by the encoders.
CONSTANT is better than VARIABLE. Use variable when you are having problems squeezing it all onto a DVD and need to make the file size a bit smaller.
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komari
Thank you all for your reponses - I'm just trully getting into the home editing this now that I have the Samsung recorder and learning alot.
neonbob: the resolution posted are as they appeared in VS cut and pasted from the file properties window! I was also not sure of the 352 x 480 when I first saw it, but it is listed in VS10. I will download VIDEOINSPECTOR when I get home tonight and confirm the properties. I also did a test and set the output resolution to 720 x 480 (against the advice given on the sticky not to change the setting) and boy did it take a long time to encode the mpeg file. By the way the resulting file size was the same as the 352 x 480 output file. From all the reading on this forum and web changing resolution doesn't affect file size much - right?
TDK1044: the files have no effects - I simply cut out the commercials and hit share/creat file and voila...resulting file if twice the size!
GeorgeW/sjj1805: I have to agree that the 10000 kpbs reported by the recorder seems to be too high - isn't that approaching HD-DVD! So if the origianal file is actually say 2-2500 kbps, then does it make any sense encoding it at 6000 kbps? Would that actually make it look worse? I'm asking base on George's statement "(but using a lower resolution in conjunction with lower bitrates might make the resulting mpeg look better). That is why in LP mode your recorder appears to have dropped to Half D1 resolution".
Forgot to add - thinking about future upgrade of TV - would keeping the bitrate low result in poor play back on an HDTV set? What would be good setting to have now so that the DVDs would look okay on a higher definition set?
Thanks once again...
KO
neonbob: the resolution posted are as they appeared in VS cut and pasted from the file properties window! I was also not sure of the 352 x 480 when I first saw it, but it is listed in VS10. I will download VIDEOINSPECTOR when I get home tonight and confirm the properties. I also did a test and set the output resolution to 720 x 480 (against the advice given on the sticky not to change the setting) and boy did it take a long time to encode the mpeg file. By the way the resulting file size was the same as the 352 x 480 output file. From all the reading on this forum and web changing resolution doesn't affect file size much - right?
TDK1044: the files have no effects - I simply cut out the commercials and hit share/creat file and voila...resulting file if twice the size!
GeorgeW/sjj1805: I have to agree that the 10000 kpbs reported by the recorder seems to be too high - isn't that approaching HD-DVD! So if the origianal file is actually say 2-2500 kbps, then does it make any sense encoding it at 6000 kbps? Would that actually make it look worse? I'm asking base on George's statement "(but using a lower resolution in conjunction with lower bitrates might make the resulting mpeg look better). That is why in LP mode your recorder appears to have dropped to Half D1 resolution".
Forgot to add - thinking about future upgrade of TV - would keeping the bitrate low result in poor play back on an HDTV set? What would be good setting to have now so that the DVDs would look okay on a higher definition set?
Thanks once again...
KO
I have a hdtv... SD looks okay on it. SJJ is correct though, you should use cbr for all your recordings, vbr is better for getting more on a disk as opposed to better quality. CBR is a steady rate, easier to work with and calculate.
When I record from tv, all my recordings are done in cbr and the bit rate is precalculated so that I do not have to change it when it is rendered. However, I do not go with a bitrate lower than 5000k. Standard dvd is 720x480. On an hdtv, I would not go lower than this (vcd or svcd).
When I record from tv, all my recordings are done in cbr and the bit rate is precalculated so that I do not have to change it when it is rendered. However, I do not go with a bitrate lower than 5000k. Standard dvd is 720x480. On an hdtv, I would not go lower than this (vcd or svcd).
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komari
Not sure that I'm reading the last sentence properly - you would not go less than 720x480, or lower than vcd/svcd resolution on an HDTV set? I know that newer HDTV upsample signals, so does that mean that even if the DVD is sending out 352x420 coded in the file, it will be displayed at 720x480 right? I will have to record everything in SP mode to the get the TV shows at 720x480, but sometimes I don't have a choice if the program(s) go more than 2 hrs. Otherwise to render everything @ 720x480 is going to be a pain in the...neonbob wrote:When I record from tv, all my recordings are done in cbr and the bit rate is precalculated so that I do not have to change it when it is rendered. However, I do not go with a bitrate lower than 5000k. Standard dvd is 720x480. On an hdtv, I would not go lower than this (vcd or svcd).
By the way, does Samsung simply invert the numbers 352x420 intead of reading 420x352 (that is what I have been assuming all along)?
Right! ...It's because of compression. The bitrate is bits per second. That can be simply scaled-up to gigabytes per hour, which determines the file size and how much playing time you can fit onto a DVD. Easy!By the way the resulting file size was the same as the 352 x 480 output file. From all the reading on this forum and web changing resolution doesn't affect file size much - right?
If the video wasn't compressed, a higher pixel-resolution would require a higher bitrate. And, a video with higher pixel-resolution has to be compressed more than a lower pixel-resolution video to get the same MPEG bitrate.
[size=92][i]Head over heels,
No time to think.
It's like the whole world's
Out of... sync.[/i]
- Head Over Heels, The Go-Gos.[/size]
No time to think.
It's like the whole world's
Out of... sync.[/i]
- Head Over Heels, The Go-Gos.[/size]
Sorry... I did a lousy job at wording that.komari wrote: Not sure that I'm reading the last sentence properly - you would not go less than 720x480, or lower than vcd/svcd resolution on an HDTV set? I know that newer HDTV upsample signals, so does that mean that even if the DVD is sending out 352x420 coded in the file, it will be displayed at 720x480 right? I will have to record everything in SP mode to the get the TV shows at 720x480, but sometimes I don't have a choice if the program(s) go more than 2 hrs. Otherwise to render everything @ 720x480 is going to be a pain in the...
By the way, does Samsung simply invert the numbers 352x420 intead of reading 420x352 (that is what I have been assuming all along)?
What I am trying to say is that vcd and/or svcd does not come out looking that great on a hdtv... It's watchable, but barely Standard dvd (720x480) is the minimum that I would go with hdtv.
There is no "upsampling" involved if you use less than 720x480. DVD players use a standard ntsc signal which has a standard 4:3 ratio (unless of course you are talking about an upconverting dvd player). There is such a thing as dvd widescreen but that's a different thing. If you use 720x480, it comes through the ntsc as 4:3 which fills your 4:3 screen. If you use 352x240, it still comes through the ntsc at 4:3 ratio and again fills the screen. The difference is that you will see much more in the way of pixelation with the 352x240 because of how much more the picture must be enlarged.
HDTV's handle a ntsc signal in different ways. Some stretch the picture. some simply zoom the picture and some do both. The more expensive ones do have upconverters.
The "mode" (sp, Lp, etc) you record in has more to do with bitrate adjustment than resolution. You can change the resolution up and down and still be in the SP mode. The terms SP and LP are simply terms developed for people who don't know too much about bitrates.
You should actually try to get used to do the custom settings yourself... it goes a long way to clearing up some of the confusion seen in this thread. It is not that hard to do. This way you know EXACTLY what you are recording, rendering and burning.
On the contrary, resolution has a big affect on file size. 720x480 (720*480=345600 dots) is about double the size of 352x240 (352*240=84480 dots) so there is about twice as much info. The file will come out almost twice as big in comparison at the same compression rate.komari wrote:
neonbob: the resolution posted are as they appeared in VS cut and pasted from the file properties window! I was also not sure of the 352 x 480 when I first saw it, but it is listed in VS10. I will download VIDEOINSPECTOR when I get home tonight and confirm the properties. I also did a test and set the output resolution to 720 x 480 (against the advice given on the sticky not to change the setting) and boy did it take a long time to encode the mpeg file. By the way the resulting file size was the same as the 352 x 480 output file. From all the reading on this forum and web changing resolution doesn't affect file size much - right?
KO
As DVDDOUG said, if you are coming out with a file size of the same, then you must be recording the 720x480 at a much higher compression.
Lower resolutions such as 352x240 are standards for VCD (Video Compact Disk)... A cd only holds about 700mb... not enough room for 720x480 (which is the dvd standard).
neonbob wrote:On the contrary, resolution has a big affect on file size. 720x480 (720*480=345600 dots) is about double the size of 352x240 (352*240=84480 dots) so there is about twice as much info. The file will come out almost twice as big in comparison at the same compression rate.komari wrote:
neonbob: the resolution posted are as they appeared in VS cut and pasted from the file properties window! I was also not sure of the 352 x 480 when I first saw it, but it is listed in VS10. I will download VIDEOINSPECTOR when I get home tonight and confirm the properties. I also did a test and set the output resolution to 720 x 480 (against the advice given on the sticky not to change the setting) and boy did it take a long time to encode the mpeg file. By the way the resulting file size was the same as the 352 x 480 output file. From all the reading on this forum and web changing resolution doesn't affect file size much - right?
KO
As DVDDOUG said, if you are coming out with a file size of the same, then you must be recording the 720x480 at a much higher compression.
Lower resolutions such as 352x240 are standards for VCD (Video Compact Disk)... A cd only holds about 700mb... not enough room for 720x480 (which is the dvd standard).
Resolution has no affect on file size using the same encoding bitrates (either the same Constant Bitrate, or the same Avg Variable bitrate).
Also, for a VCD that is burned properly in VCD mode, you can burn about 800mb onto a regular 700mb CDR.
Regards,
George
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maddrummer3301
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komari
Okay - so it looks like the problem is not with VS10, but rather with Samsung. Bear with me cause it's going to be a long post...
As neonbob suggested, I downloaded VideoInspector and I also went back to the DVD-recorder (Samsung R130) to see if I can fine tune the recording setting. I didn't remember seeing an option to do that, and there isn't other than setting the EP mode btw 6 vs 8 hrs. But I also went back to the manual and saw something that I had skimmed over: XP = 1h, ~8Mbps; SP = 2h, ~4Mbps; LP = 4h, ~2Mbps; EP = 6/8h, 1.2/0.8Mbps. So that was in line with what GeorgeW had said that the original mpeg was at between 2-2.5Mbps.
Now here's the weird part, as shown in the original post, according to VS10 the mpeg I imported (recorded at LP mode) had a bit rate of 10Mbps! Both files also had identical audio settings. I went ahead and opened both files using VIDEOINSPECTOR and this is what I got:
Original mpeg from Samsung R130:
Movie - File Size: 2.04 Gb, Valid: Yes (MPEG), Movie complete: Yes, Duration: 00:00:01
Video - Resolution: 352x480 (0.73:1), FPS: 29.97, Bitrate: 9766 Kbps, Quality factor: 1.97b/px, Code: MPEG2
Audio - Number of channels: 2, Sample rate: 22050 Hz, Bitrate: 64 Kbps, Codec: MPEG Audio 1 layer 3 (MP3)
Output DVD-NTSC mpeg from UVS10:
Movie - File size: 3.9 Gb, Valid: Yes (MPEG), Movie complete: No, Duration: 01:45:52
Video - Resolution: 352x480 (0.73:1), FPS: 29.97, Bitrate: 5859 Kbps, Quality factor: 1.18b/px, Codec: MPEG 2
Audio - Number of channels: 1, Sample rate: 22050 Hz, Bitrate: 8Kbps, Codec: MPEG 2 Layer 2
Just for kicks to see what the difference would be, I also opened a 2 1/2 hr video which was recorded at SP mode on the Samsung recorder:
Movie - File size: 2.57 Gb, Valid: Yes (MPEG), Movie complete: Yes, Duration: 00:00:01
Video - Resolution: 720x480 (1.5:1), FPS: 29.97, Bitrate: 9766 Kbps, Quality factor: 0.97b/px, Codec: MPEG2
Audio - Number of channels: 2, Sample rate: 16 Kbps, Codec: MPEG Adio 1 layer 1
So as you can see the audio properties are all over the place in VIDEOINSPECTOR, although they are all reported as the same in VS10. The only difference between LP and SP according to VIDEOINSPECTOR is the Resolution, Quality and Audio setting. The bitrate is reported to be the same although it is not as stated in the Samsung manual! Does anyone know what the b in the Quality factor stand for - this appears to be the only value that actually seems to make (inverted!) sense. Why does the number of audio channels drop to 1 in the DVD output Mpeg?
What do you guys think - Samsung has a weird way of coding it's mpeg files which is confusing VIDEOINSPECTOR and UVS? The model I bough just came out 05/2006, and I don't have anything to compare it too (it is my first DVD-recorder).
Now the only thing I'm still not clear about is whether rendering the obviously 2-2500 Kbps original mpeg at 6000 Kbps would actually make it look worse. As George mentioned earlier, it might be better to use a low bitrate setting since it is at a lower resolution (352x480). But for future playback on an HDTV I would have to output the files at 720x480 and no less that 5000 Kbps to get satisfactory results - right neonbob?
Thanks a whole bunch all of you...
KO
As neonbob suggested, I downloaded VideoInspector and I also went back to the DVD-recorder (Samsung R130) to see if I can fine tune the recording setting. I didn't remember seeing an option to do that, and there isn't other than setting the EP mode btw 6 vs 8 hrs. But I also went back to the manual and saw something that I had skimmed over: XP = 1h, ~8Mbps; SP = 2h, ~4Mbps; LP = 4h, ~2Mbps; EP = 6/8h, 1.2/0.8Mbps. So that was in line with what GeorgeW had said that the original mpeg was at between 2-2.5Mbps.
Now here's the weird part, as shown in the original post, according to VS10 the mpeg I imported (recorded at LP mode) had a bit rate of 10Mbps! Both files also had identical audio settings. I went ahead and opened both files using VIDEOINSPECTOR and this is what I got:
Original mpeg from Samsung R130:
Movie - File Size: 2.04 Gb, Valid: Yes (MPEG), Movie complete: Yes, Duration: 00:00:01
Video - Resolution: 352x480 (0.73:1), FPS: 29.97, Bitrate: 9766 Kbps, Quality factor: 1.97b/px, Code: MPEG2
Audio - Number of channels: 2, Sample rate: 22050 Hz, Bitrate: 64 Kbps, Codec: MPEG Audio 1 layer 3 (MP3)
Output DVD-NTSC mpeg from UVS10:
Movie - File size: 3.9 Gb, Valid: Yes (MPEG), Movie complete: No, Duration: 01:45:52
Video - Resolution: 352x480 (0.73:1), FPS: 29.97, Bitrate: 5859 Kbps, Quality factor: 1.18b/px, Codec: MPEG 2
Audio - Number of channels: 1, Sample rate: 22050 Hz, Bitrate: 8Kbps, Codec: MPEG 2 Layer 2
Just for kicks to see what the difference would be, I also opened a 2 1/2 hr video which was recorded at SP mode on the Samsung recorder:
Movie - File size: 2.57 Gb, Valid: Yes (MPEG), Movie complete: Yes, Duration: 00:00:01
Video - Resolution: 720x480 (1.5:1), FPS: 29.97, Bitrate: 9766 Kbps, Quality factor: 0.97b/px, Codec: MPEG2
Audio - Number of channels: 2, Sample rate: 16 Kbps, Codec: MPEG Adio 1 layer 1
So as you can see the audio properties are all over the place in VIDEOINSPECTOR, although they are all reported as the same in VS10. The only difference between LP and SP according to VIDEOINSPECTOR is the Resolution, Quality and Audio setting. The bitrate is reported to be the same although it is not as stated in the Samsung manual! Does anyone know what the b in the Quality factor stand for - this appears to be the only value that actually seems to make (inverted!) sense. Why does the number of audio channels drop to 1 in the DVD output Mpeg?
What do you guys think - Samsung has a weird way of coding it's mpeg files which is confusing VIDEOINSPECTOR and UVS? The model I bough just came out 05/2006, and I don't have anything to compare it too (it is my first DVD-recorder).
Now the only thing I'm still not clear about is whether rendering the obviously 2-2500 Kbps original mpeg at 6000 Kbps would actually make it look worse. As George mentioned earlier, it might be better to use a low bitrate setting since it is at a lower resolution (352x480). But for future playback on an HDTV I would have to output the files at 720x480 and no less that 5000 Kbps to get satisfactory results - right neonbob?
Thanks a whole bunch all of you...
KO