![]() |
Problem with vegas capturing video from DVX
Hello people. Please check this image:
www.bachibuzuc.com/vegasproblem.tif This is one of the many clips that are not very well captured with vegas. The problem as you see is that the red color is unaceptable bad. I have seen this problem also with interalced video from canon xl1 in ulead video editor and vegas 3. But with dvx100 progressive video, it is even more obvious that the red color is not very good captured. So what can i do? Do you guys have the same problem? Any help? |
when you transfer from TAPE ( camera) to hard drive over 1394 only DATA is transferred.
IMO there is nothing wrong with the color RED ?? perhaps what you are objecting to is the INTERLACING around it ... i see that your preview windows says preview 720X576x32 ; 25.00i .. also the project has the same spec's .. it appears you have your project set up as INTERLACE not progressive. try setting it up as progressive ..Vegas 4.0b is set up to handle the DVX 24p ... i assume you have the PAL version so in V3 or V4 .. to change your current project to progressive FILE /properties/ Video then change the field order to PROGRESSIVE ... to set up new projects FILE /NEW/Video ..change field order to PROGRESSIVE if you want all NEW projects to be set up as progressive be sure to CHECK the BOX "start all new project with these settings" sorry for above i assumed that because you shot with DVX you shot progressive ... but appears you shot INTERLACE ... |
Let see. It is not a problem of the vegas settings.
I am using PAL as you can see. When you outputs d video via firewire from the camera, the computer software has to recompress it all again. Forget about the loss of quality with iee1394. THere is always a recompresion using the software that you use. The red is not well handled with standrad dv codecs and things like the picture y posted occur. It is not a problem of setting fields in vegas. |
sorry but you are mistaken. when you output from camera over 1394 the computer software does NOT recompress it ... the camera compressed the data when it recorded the imges to tape ... from tape the DATA is transferred to your hard drive .. the only thing your software does is put a "header" on the clip to say if it's a AVI if on a PC and a MOV header if on a mac.
sorry I asumed you shot progressive because this is a DVX 100 my mistake ..... WHAT is wrong with your REDS ?? RED color looks very good to me .. the only thing i see are interlace artifacts around the reds and according to your NLE it see's the clip as interlace ... |
i bet you 100 that when you transfer video from the camera to the pc it is actually recompressed.
What are the comparison between same clips captured in differente programs (ie: vegas, avid dv, fcp, ...) |
Don is correct, no recompression of data in just the transfer. Data is data, 1 or 0. The only time the data is altered is if the data is changed (graphics keyed, color correction, resized etc.). If you render then you change the data. Just putting it on your drive or viewing it in your NLE has no effect.
|
Then how do you explain different DV codecs, and different image qualities with the same sources?
Right now i just did another try with avid dv express 3.5 and the artifacts that you see in the reds are minimized. The truth is that computer recompress all over again when importing from the camera. That is different when you work in the editing software and render a final video. Then, if the clips were not altered (filters, croping,...) the quality is the same, because there is no recompresion. If you do not belive me go and try yourself. Find a very saturated red t-shirt, record it with your DV camera, capture the video, and without touching anything just take the video back to the camera. You can do this a couple times to enhance the loss of quality and you will se how the red becomes more soften. Go to any website where capture images are compared between fcp and avid dv 3.5 and you will see how avid captures better than fcp and any other software. Why? If there is no compression? The reason is that there is actually compresion and avid uses his own "avid DV codec", wich is not microsoft nor quictime DV codec. Bye ;-D |
SO the question is actually what are the diffences between various capture codecs?
|
Miguel, I will point you, where I've pointed many before you, to Adam Wilt's web site. Read the section on FireWire (IEEE 1394) and Hard Codecs vs. Soft Codecs and it should all become clear. If you have additional questions feel free to post again.
|
I am sorry, but no one here has talked about hardware codecs. We are talking about software codec.
The question is very simple. Read this phrase from Bill Angstrom: "...diffences between various capture codecs?" CAPTURE CODECS. If it were just simply downloading video files, we wouldnīt use he word capture. The video cameras companies have been saying since iee1394 was launched that there was no quality loss because it is all digital. Well that is truth in only a way. It is truth that the firewire cable is digital and digital signals are the same in the begining and the end of the cable. there is no loss of data between conections as it happened with analog I/O. the thing that they do not say is that recompression occurs when importing in the computer and when importing in the camera. Again, you go and try the expirement i said and post the results. please |
OK, since you don't want to spend the time to read and learn, I'll quote from it.
Quote:
|
;-D yes i have read it. But i think that might be in theory, In the practice, there are differences between dv codecs, and the more you transfer for and from the camera the worst the image becomes.
I will give you some images that you probably have seen. |
Sorry, its a fact. Every camera manufacture and every software company will tell you the same thing. There is no change if all you do is transfer the data back and forth over 1394. The term Capture Codec is a hold over from the early days of Avid when the source material was all analog. Today, with DV, there is no capture codec.
If there was a difference, don't you think Avid would be promoting their capture codec as the best? Avid doesn't do it (or any other company) because their is no capture codec over 1394. |
Actually avid dv express does include their own dv codec.
Check this comparison: http://www.24p.com/codecs.htm |
Well, maybe i am wrong in all that i said, but this thing is the truth:
- when i capture dv video in ulead video editor and then back to the camera, a red car appear soften and not as good as the original one recored. If there was no quality loss in the capturing, where was it? (the video was not touch in any way). - the same now with vegas and my dvx100 explain me something, please or i will get finally mad.- |
They almost all have their own codecs. They are used for render and playback, but not transfer from camera to deck or camera to NLE.
|
please, read my last post.
How do you explain the difference in color in fcp and avid dv express? |
Your link to the Avid and FCP comparisons has a link to Adam Wilt's page for an explanation. Read his explanation on exporting images from FCP (difference in screen gamma of 1.8 and 2.2).
|
Well, maybe i am wrong in all that i said, but this thing is the truth:
- when i capture dv video in ulead video editor and then back to the camera, a red car appear soften and not as good as the original one recored. If there was no quality loss in the capturing, where was it? (the video was not touch in any way). - the same now with vegas and my dvx100 explain me something, please or i will get finally mad.- |
If you're talking about the screen capture, we are back to Don's comments and I agree. The red seems to be showing the interlacing artifacts. Try using progressive, you might be happier. Progressive is one of the big advantages of that camera. Is there a reason not use it?
|
arrrggg, do you think i am stupid??
the sample i gave you is shot in 25p, it is set as progressive video in vegas, and for some reason the project was in interlaced. But that gives no difference at all. if you want i give you the same capture frame with progressive video in the project settings. It is NOT a problem of setting. It is a problem of the CAPTURING!!!!!!! as i write before, i have a lot of similar videos shot with canon xl1, and sony vx2000 which look exactly the same. Red cars that show artifacts. Again it is a problem of capturing. You see the video rigth in the screen. you capture it. And upload again to the camera, and thatīs it. The red borders are soften. |
If you look at your footage on something other than a computer monitor, what do you see?
|
here you are now: www.bachibuzuc.com/vegasproblem2.tif
shot with dvx100 at 25p captured in vegas4 set as progressive video set as progressive project |
i see the footage in a tv monitor conected to the camera. when watching the original video it looks ok, when looking at the video that is being output from the PC to the camera and then to the monitor the red saturated t-shirts or cars appear slightly compressed, soften, as a jpg.
|
That link returns an error.
|
try again, i edited the post because there was an error. ;-))
|
what you are seeing are the differences between the different codec's ...
the data goes from tape to HD ... now if you use Vegas it will play back that data using SOFO codec. if you use avid to play back the file it will use avid's dv codec if you use ulleads media studio i think it uses the microsoft Dv codec if you use premiere and you have a canopus board then it will use canopus DV codec to play back the data if you have premiere set up as OHCI then it will use the microsoft dv codec to play back the data - there are ways to tell it to use different codec's if you are on a PC and you just click on a dv avi file then your computer will use windows media player and the microsoft dv codec to play back the file if on a mac and you click on the same file it will use QT dv codec to play it back you are correct that you do see different shades of REDS with each codec ... again data is just transferred from tape to hard drive .. a PC will put a header that says this clip is a dv .avi .... if on a MAC then it will put a header that says this is a DV.MOV clip ..same data just different headers ... |
Here is even more test:
- canon xl1 either at interlaced or progressive to pc with pinacle dv studio plus and using ulead video editor: artifacts - sony vx2000 interlaced to desktop computer using vegas 4: artifacts - dvx100 at 25p to this computer using vegas4: artifacts - dvx100 at 25p in a similar computer using avid dv express 3.5: less artifacts, but still some. This artifacts only appear in zones with very saturated colors and smooth surfaces as i said, cars and t-shirts for example. It is the dv codec wich losses quality. why? |
You are seeing the different codecs in use, because you are outputting the data to your PAL monitor or your computer screen. In some software the computer image is not full resolution, I don't know about Vegas.
|
what do you mean? i did not undersant your explanation. thanks
|
SOFTWARE codecs do not re-render the original DV info. It's a straight across COPY. HARDWARE codecs DO decompress / recompress. Also, hardware codecs tend to be proprietary, particularly the Avid codec. This was the single biggest reason I never invested in Avid, Who needs it.
|
From the Avid site:
"Seperate Avid Dv Codec for creating Avid compatible media in After Effects and other popular applications. The Avid DC codec also provides higher quality DV playback and is freely distributable so that media may be used on a seperate workstation that does not have an Avid Xpress DV installed". One of the reasons I went with Avid in the first place. |
Miguel, when you play back the tapes to a monitor you are using the codecs. If you see a difference, it is because of the different codecs (Vegas, Avid, ULead). Do you know what codecs are presently installed on your computer?
|
So you mean there are differences in the codecs??????
Didnīt you say that they were all the same quality??? |
let it go miguel
|
I have also some problems with the red color on a pal XM2 Canon (GL2)
I have a trick for that, I'm shooting in 16/9 mode for criticals projects. Try it ! |
WHat is the advantage of shooting in 16:9. With my old XL1 i had the same problems with the saturated reds.
By the way, how good is the camera? any difference with the GL1? |
The advantage of shooting in 16/9 is there is less bleed and less block in the red. (I don't know for others cams, but for the XM2, it works)
I haven't compare the XM2 to the XM1 (GL1), but what I know, is the XM2 is capable to make great images. |
All times are GMT -6. The time now is 05:21 AM. |
DV Info Net -- Real Names, Real People, Real Info!
1998-2025 The Digital Video Information Network