AVS HD 709 - Blu-ray & MP4 Calibration - Page 56

On most digital displays if you set brightness high enough to flash 17 then the two above black stripes will show on DVE. I suppose maybe the brighter levels in the DVE pattern is causing the stated behavior with the display, in which case using the 2nd APL pattern might make more sense with this disc. Anyway, if the difference is only one click I'd probably use the higher setting and then look at the APL pattern to double check that below black levels (under 16) don't flash. If the below black bars flash on the APL pattern that would indicate that brightness is set too high, but odds are that the higher setting from DVE will probably make 16 appear as the darkest shade on the APL pattern.

Sure that's the sort of thing that could be created by the process we use. I don't own a plasma and consider it slightly off-topic from calibration, but I can see how such a thing could be useful. Basically my perspective is that I'd rather tell someone how they could do this, rather than necessarily to do it myself. So if someone wants to take the lead and create a plasma-related HD pattern, I could help with the step by step how to do it.

The general process we use here to author to Blu-ray is basically four steps:

1) Create a 1920x1080 image and save as 24-bit .tga
2) Convert .tga to .yuv
3) Encode video from .yuv
4) Author video to Blu-ray compatible disc


STEP 1 – CREATE IMAGE

Paint.net or Photoshop are two programs that are able to save to 24-bit .tga images, but I'm sure there are many other image editing programs able to do the same. All of the video used in the project is 1920x1080, so that will be the expected image resolution. Generally just keep the RGB values between 1 and 254, or 16 to 235 if you want to stick to the black to white range. If all R, G, and B are equal you have a gray, and for example if one color is at 235 while the others are 16 you have a primary color. There should be information online for how to use different image editing software, so the most important item is that at the end of this step you need to save to a 24-bit .tga file with a 1920x1080 size.

In the attachment, example.tga is the expected sort of image to have at the end of this step.


STEP 2 – CONVERT TO .YUV

For this step we use a program from dr1394. rgbtouyvy.exe is explained in http://www.avsforum.com/avs-vb/showt...7#post12165597 or the yuv.bat from the attachment will work on the example.tga image.

With the attachment, you can use the yuv.bat to convert example.tga to example.yuv to complete this step.


STEP 3 – ENCODE TO VIDEO

We encode using http://sourceforge.net/projects/megui/ and http://sourceforge.net/projects/avisynth2/files/ After installing those two programs you also need to extract http://avisynth.org/warpenterprises/...l_20060728.zip into the Avisynth plugins directory. Once you open MeGUI allow the program to update and install the profiles. Click “...” by AviSynth script to select a .avs file for encoding, by encoder settings choose the x264: standalone AVCHD option (spelled slightly differently), and by file format choose the raw .264 setting.

The example.avs in the attachment is setup to encode approximately three minues of video. You will need to change C:\\example.yuv to the path where example.yuv is located, and after doing that you can use the file for your AviSynth script to encode the example (or just put the .yuv in C:\\). The .avs file can be edited to display different images, for example flashing.


STEP 4 – AUTHOR TO BLU-RAY

There are a number of programs that can author .264 video to Blu-ray compatible files. MultiAVCHD and TsMuxer are free programs, or there are a number of commercial programs. If the program authors to AVCHD folders and you want to burn to DVD media, then you need to burn to UDF 2.5 or 2.6 like described in step 4 from http://club.cdfreaks.com/f142/bd2dvd...-guide-232165/ Generally creating disks compatible with Blu-ray players is discussed in http://www.avsforum.com/avs-vb/showt...815296&page=65


Anyway, that's the general overview of how to author chosen images to Blu-ray compatible video. If there are specific questions of problems encountered, and what to do with different steps, I can address those items. The example.zip attachment should contain the following files:

example.avs
example.tga
rgbtouyvy.exe (49,152 bytes)
yuv.bat

Note1: Some more example files, and my x264 video encode settings are included in http://www.avsforum.com/avs-vb/showt...1#post21567091
Note2: If you would like to place multiple images in the same video, see the .avs attachment from http://www.avsforum.com/avs-vb/showt...1#post21564901
Note3: How to check video levels from encoded video is mentioned in http://www.avsforum.com/avs-vb/showt...9#post21583899

 

Example.zip 34.1865234375k . file

The third pattern under Basic Settings is generally intended for looking at clipping for contrast. There are PDF files in the first post with further descriptions of the main patterns, including that one.

If you set brightness as low as possible so that 17 just barely flashes, then generally black should be as dark as the display is able to produce. On most displays going lower with brightness than where 16 stops flashing (assuming TV can display below blacks) will not actually make black any darker, but it's possible that it may on a few displays. You can observe how your TV performs by turning down brightness on the black clipping pattern below the recommended setting. Most likely if you use a lower setting the level where clipping starts will change, but the actual brightness of the clipped portion will probably be about the same.

The digital displays I've looked at generally don't make the darkest portion any darker by turning down brightness, so I have to figure that what you're really talking about is either the darkest level the display can produce or else gamma.

DARKEST LEVEL:
If the display is an LCD then it might have a backlight adjustment, and by turning down the backlight then the light output will be lowered and the darkest level will be darker. Having more light in the room may also change perception so that the darkest level appears darker.

GAMMA:
Gamma is basically how light changes between the darkest level and the brightest level. The first couple patterns in Misc Patterns Section A can give you an idea if any controls on your display, except for brightness and contrast, affect how the TV increases brightness between black and white. By turning down brightness below the recommended setting you are effectively raising gamma, and cutting off information intended to be displayed. I am not familiar with your display, but some displays will have additional controls, besides brightness and contrast, that will affect the light output for levels between black and white.


To sum all of the above up:
- Going lower with brightness probably doesn't make black any darker.
- Turning down a backlight on an LCD would make black darker, and more light in the room may affect near-black perception.
- Some displays will have additional controls to change how light increases between black and white. If that's the case with your TV then those controls may allow you to darken near-blacks, otherwise using a lower than recommended brightness setting would have a similar effect of making near-blacks darker.

I'd suggest sticking to BD-RE so the disc can be reused. I just have some BD-RE I picked up at microcenter, but if you have to order meritline or newegg are usually reasonable. You don't say what operating system you're using, but Vista SP2 or Win7 can format and burn Blu-ray without any other software. I think I might have used Imgburn for Blu-ray at some point, but generally I just use windows explorer and right click on the drive to format the disc and then copy the files over.

I took a quick look at Nero 8 on my computer. UDF is set to automatic so I have to assume they get that right. The only thing I would question with Nero is that my version defaults to multisession.

The general method of troubleshooting is:

- Which version are you using?
- Did you happen to check the hash on the download or .iso?
- Did you burn with a program like Imgburn to verify the burned disc?

Beyond that there isn't enough information for me to backcheck to see if I'm getting the same behavior. There is a reported chapter navigation item I have corrected for the v1.3 HDMV and PATCHED versions, which hasn't been released, but otherwise no one has mentioned any other authoring issues so far.