Need your experience

[JPD]

When doing an AVI file with PTE or a DVD, the colour of the AVI on a PC or of the DVD on a TV or on a PC isn't the same as the PTE file.

On a PC, if I succeed to don't use the overlay, for instance if Windows Media was reading an AVI file and I stop (pause) it and then I read with another tool the AVI file I am testing, the color is the same as in PTE, but if the AVI file I test use the overlay, the color isn't at all the same.

I see the problem on my 3 PC, and I search the reason. On one of my PC I have a Radeon 7500, and I saw that for overlay there is a color correction : brightness = + 12% and contrast = 123%.

I try to compare a picture where I put the same value, and it give the same result as for the AVI file.

I search on the net if there was a reason and maybe found an explaination :

The commercial DVD would have all the informations between 16 and 235, so the overlay make a correction in order these value become 0 and 255, with more brightness and more contrast, but it does the correction for all the video files, so it would be the explanation.

I have make an exe with PTE, the exe launch an AVI file with the same picture than those of PTE with the Granot's utility, so it's easy to see if there is a difference. I change the PTE pictures with the same with Brightness = 12% and Contrast 23 % and there was no difference.

I did also the test with normal picture, but without overlay, and the color of PTE and AVI where also the same. I made an exe which launch an AVI (all is in the same exe, I used Winrar to do it), in order you can see what I mean, it's here .

Did somebody can confirm (or not) the explaination I found, and which method you use in order to have good DVD (or AVI/MPEG file).

Would it not be necessary to have an option in PTE to correct this problem when doing an AVI file ?

Note : I use Microsoft mpeg4 v2 Codec, but it seems there is the same problem when burning a CD whith ptev and ulead factory 2.

I searched about this problem in the forum and didn't find anything, but it's not easy for me to understand all is write.

[Ken Cox]

JP

I dont know what you mean by"overlay"

i put your hubble show on my tv's via the svhs output of my ati 9000 all in wonder graphics card and can see a very slight change in the letters floating across the screen -- yellow/gold on the tv -- less gold on my 19" samsung lcd monitor -- more yellow

but nothing to get excited about

except for the testing we have run here

http://www.picturestoexe.com/forums/index.php?showtopic=3943

and here

http://www.picturestoexe.com/forums/index.php?showtopic=3992

I always use the pte default settings and import the avi into nero to make the dvd. On Al Robinson's recent trip he dropped off a test dvd of his and one of Hawks and the whites were dead on when viewed on the tv at my place and at other hd ws tv's where i can test.

Lin Evans riva, exe, and flv shows are dead on for colours on the tv and monitor

I checked my new monitor for colour accuracy with a scanned image of a macbeth colour checker and i verified the brightness levels with

the monitor check here

http://www.eye4u.com/home/

Maybe if you could make a test show using known values -- whites [white house white truck/car]and not clouds you may be able to sort out what is going on

ken

[JPD]

Thanks Ken, I read the pages you give, but I don't found anything about the problem that I have.

If I well understand, the overlay is a picture calculate directly by the graphic card, without using the CPU and which is above the picture of the screen, so it's impossible, for instance to copy these picture in the clipboard with the screen copy function.

These pictures exist only when using "material acceleration" (it's a translation from french and am not sure it's the right word in english)

If I don't use "materiel acceleration" of the graphic card, the color are right, but if I use it, the pictures have brightness and contrast modified.

It's easier to see the difference of color in the white part of the earth, when the AVI file is running, it's more white than when it's PTE which is running.

I am not sure to understand what you mean with "and the whites were dead on " but may be it's the reason I try to explain above which make the white more white.

[Lin Evans]

Thanks Ken, I read the pages you give, but I don't found anything about the problem that I have.

If I well understand, the overlay is a picture calculate directly by the graphic card, without using the CPU and which is above the picture of the screen, so it's impossible, for instance to copy these picture in the clipboard with the screen copy function.

These pictures exist only when using "material acceleration" (it's a translation from french and am not sure it's the right word in english)

If I don't use "materiel acceleration" of the graphic card, the color are right, but if I use it, the pictures have brightness and contrast modified.

It's easier to see the difference of color in the white part of the earth, when the AVI file is running, it's more white than when it's PTE which is running.

I am not sure to understand what you mean with "and the whites were dead on " but may be it's the reason I try to explain above which make the white more white.

Are you watching the AVI after conversion to DVD on a PAL television or are you watching the AVI file only on your computer?

The reason I ask is that there are changes on a television because it can't display the same number of colors as your computer and some codecs allow decreasing the brightness by some amount to compensate for the differences between a television and the computer. If the brightness levels are not decreased for the conversion to DVD then the colors will appear washed out or less intense on the TV.

I "think" what your translator is calling "material acceleration" is what is known as "hardware acceleration" on the Windows setup for any particular graphics card. I can't think of any good reason why hardware acceleration would affect the color, but this is a question better answered by Igor.

If you could link to a sample of the AVI as well as original jpg's used to create the AVI perhaps others can see the differences and maybe offer suggestions.

Best regards,

Lin

[JPD]

I did the comparison on my 3 PC, it's the easiest to do, and also on Secam TV, but the comparison on a TV is more difficult to do.

I have use the same codec as you used, but it seem to be the same thing when using a DVD made whith Ulead from the PTE codec, I must do others test to be sure.

There is really a difference between using or not "hardware acceleration" function when viewing an AVI file.

In the sample I give here the begining and the end are PTE files and all the pictures where Hubble is are AVI pictures.

I will prepare another sample.

I "think" what your translator is calling "material acceleration" is what is known as "hardware acceleration" on the Windows setup for any particular graphics card

You are right, it's seem to be the correct word.

I can't think of any good reason why hardware acceleration would affect the color

The harware acceleration change the color on my different PC. The reason is maybe to correct the commercial DVD which would work only between values 16 and 235 in order to have at the output of the harware acceleration a value between 0 and 255, but I am not sure of this explanaition.

[Ken Cox]

JP

"and the whites were dead on "

by this i mean there is no colour tint in the shadows of white sections -- o -- proper rendered white, the shadows will be grey.

I used the 2 threads only for reference and only to show the procedures we were using to achieve the the format for tv - we were not faced with your problem.

ken

[JPD]

I have made a little exemple here with 3 pictures in the AVI file (576 x 768).

The first one is made of 16 parts with 16 grey levels from 0 to 255, the second one with 16 levels of grey between 16 and 235 as I read on the net about commercials CD, and the third one with 16 differents colors in order it's near the same as PTE grey scale with my graphic card (ATI - Radeon 7500, screen Viewsonic P95f+) when hardware acceleration is used.

A pte file with only one picture of 1024 x 768 with exactly the same grey level as the 1st AVI picture lauch the AVI file, so we can easily compare the colors.

The AVI pictures are in the middle.

There are 2 PTE files, the first one, AVI.pte is used to create the AVI file and the second, Overlay.pte to compare the colors.

If the hardware acceleration isn't used, we don't see any difference between the 1st AVI picture and the PTE picture, if yes, there is a big difference with my PC.

If the hardware acceleration is used, there is a big difference between the 1st AVI picture and the PTE picture and a very little difference between the 3rd AVI picture and the PTE picture.

All the pictures are in the zip file.

I hope to succeed to be understand, excuse me for my bad english.

[JPD]

by this i mean there is no colour tint in the shadows of white sections

I understand that your picture is brighter than the original one. Am I right ?

[Ken Cox]

JP

i am going by what i was taught when printing colour in the darkroom -- if shadow areas are not a neutral gray colour then you have the wrong colour balance for the picture/print -- colour correction in the darkroom should be the same as digital pictures.

I believe a colour analyzer takes all the colours in a picture and converts them to a shade of grey -- thus the neutral grey card's 18% reflectance -- in some myy old Kodak books they used to say put a grey card in the first picture of a roll as a known value.

Then one has to compensate for flesh tones

the cameras today have the smarts built in to correct the operator errors:)

ken

[Ken Cox]

JP

your

MIRE 16-235.BMP

shows proper separation of the white to black as described on

the eye4u

http://www.eye4u.com/home/

monitor test

ken

[JPD]

I have find that on my 2 PC which are abble to read DVD, if I open Windows Mediaplayer with a file, made a pause and then open the DVD with another player, the colors are good and are the same than with the PTE exe file (the colors corrections of the overlay doesn't work) and are better that those of the same DVD when I read it without opening Windows Mediaplayer (or another one) before and of course better than on TV.

The hardware acceleration change the color on my 2 PC, it must probably be the same for other PC, and the color is also change when I use my DVD player with TV.

When we create a DVD with PTE codec or another one plus DVD movie Factory, the datas in the AVI files are he same as with PTE, but all the system which read DVD directly seems put a correction so the colors of the picture haven't the same level. So I think it's necessary to have a good DVD we must corect the colors before to do it.

Does somebody knows a tool to do that ?

[Ken Cox]

JP

A dvd played on your monitor is going to look better when played on a dvd/tv set up i belive -- this has been mentioned before -- wmp is not the ideal place to play a dvd and wmp has separate colour, tint contrast controls etc which likely will affect your viewing on the monitor

when i make a dvd i play it immediately in the tv/dvd setup -- the computer has just been the tools to make it

ken