The Analog Video CVBS Conversion to Digital Video HDMI Controversy

   

The best and only method of capturing and converting analog video to digital is via a PC interface. It is a straight through video conversion that transfers data in its original aspect ratio and color depth without conditioning. Any enhancements that need to be done to the video are performed with digital software on the destination computer hardware.

There are NO converters that will support converting CVBS RCA analog component/composite to FULL 0-255 color space via HDMI .  Every one of these converters from a $9.00 Wal-Mart special to the very expensive Aten, Black Box, Kramer, KanexPro, and or other costly converters will only output LIMITED 16-235 color space via HDMI .  It seems there is only one chip manufacturer in China and every one of these converters uses that same chip. 

Explanation

NTSC - National Television System Committee, are an American set of standards for analog television color system that was introduced in North America in 1954 and stayed in use until digital conversion.

ATSC - Advanced Television Systems Committee standards are an American set of standards for digital television transmission over terrestrial, cable and satellite networks.

In our quest for an inexpensive method of converting 4x3 640x480 analog videos to be viewable on a 16x9 1920x1080 widescreen HD PC monitor, we’ve contemplated, considered and tried many methods to no avail. There was always something that went wrong.

It is now over 20 years past the Y2K analog to digital transition and we as the US are well into High Definition 1080 digital video and entering the 4k and even 8k realms. However, unlike audio, much of our legacy 480 videos most people have accumulated are not easily and comfortably viewable on high def digital TVs and PC monitors. While attempting to convert or transfer video content, the user is fraught with complications, poor performance and distortion.

Though there are countless adapters available that range in price from 6 to $270, all of these have proven to be subpar at best. They are plagued with out of sync sound and video, faded images, poor focusing, inaccurate color and stretching or skewed images. The CoolDigital converter (bottom right) is an inexpensive tiny $12 box that does at least have the option of maintaining the correct aspect ratio. The rest that have this feature cost well in excess of $150.

It seems people don’t understand that most television programming and home videos made prior to the year 2000 have a CRT based aspect ratio of 4x3. This format is meant to be viewed in its original format. Just because someone has a flat panel wide screen TV, doesn’t mean they can see these old videos in high definition. This material will not even appear appropriately on a widescreen TV unless the 4x3 image is centered in the middle of the display with black bars on either side. Sorry, that’s the way it is. Sure, one can stretch the image to fill the entire 16x9 display. But the image will be distorted making people and objects appear fattened. Basically and fundamentally, there’s no data to fill in the black bars. That’s why they are there indicating missing data.

As for resolution, again we purists apologize. There’s no high definition data in these videos. The resolution of the media is what will be seen on an HDTV – which is within an absolute maximum bandwidth of 650x535 resulting in 640x480 30 fps interlaced. This was the NTSC analog standard of the time. However, videos recorded by most home enthuses have a resolution of about 320x240. Again, sorry. If you owned a standard definition home VCR, you know how much they cost. You weren’t about to plunk down 10 to $30,000 in 1980s dollars for a broadcast quality video recorder. Even your first generation tapes will look rather lousy on an HDTV. As for Super Beta, these were little better. As for SVHS and ED Beta, these were even better, but, still, on an HDTV you’re not going to see high def?

Sure, there are methods of synthesizing a slightly clearer picture, but for the most part, it’ll still result in the 1950s NTSC TV standard.

There are converters that can employ a zoom feature of magnifying a 4x3 image to make it appear to be 16x9. But again, there is not enough data to convert the 640x480 dots into 1920x1080 dots. Also, this zoom process will crop the top and bottom portions of the 4x3 image. Meaning, the viewer loses that part of the image and the resulting video is presented at an even lower resolution of 640x360.

It seems the process of converting an improved image such as what is seen on a commercial television rebroadcasts will come at a significant cost and will necessitate a great deal of skill to operate the hideously expensive digital synthesis equipment.

These companies who claim their inexpensive little devices that do it all are in reality snake oil sales people - as we and others alike have discovered – and ended up returning to Amazon.


CoolDigital HD Video Converter upscaler 1080p AV to HDMI

The above tiny 2” wide $12 converter is the only one we kept for now because it does keep the correct 4x3 aspect ratio. However, this converter is spec'd for ATSC standard (limited 16-235) HD televisions, not (full 0-255) computer monitors where converted videos will appear washed out.  Also, it does not have a model number or anything else to distinguish it from others with the CoolDogital label on them that appear to be similar.

This 2018 converter is no longer listed on Amazon. In fact, it’s now very hard to find.

Note. It must be understood that the majority of users who purchase these converters are not interested in watch vintage television or home videos. Rather they seek to attach their older video gaming equipment to their large screen televisions.

VHS to HD – You can’t make a silk purse out of a sow’s ear.

 

  Video Parameters

Analog Standards

NTSC 525 lines Interlaced @ 30 Full Frames Per Second, 60 Scans Per Second

PAL 625 Lines Interlaced @ 25 Full Frames Per Second, 50 Scans Per Second

  

Analog Resolution

Standard Luminance Resolution Chroma Resolution
VHS (NTSC) 240 lines 320×486 30 lines 40×486
VHS (PAL) 240 lines 320×576 30 lines 40×288
Beta (NTSC) 290 lines 378×486 30 lines 40×486
Beta (PAL) 290 lines 387×576 30 lines 40×288
S-VHS (NTSC) 420 lines 560×486 30 lines 40×486
S-VHS (PAL) 420 lines 560×576 30 lines 40×288
ED Beta (NTSC) 500 lines 667×486 30 lines 40×486
ED Beta (PAL) 500 lines 667×576 30 lines 40×288

  

Digital Resolution

Standard Resolution Frame Rate Type Comment
720p DVD 1280×720 60 FPS Progressive Standard Definition
1080i ATSC 1920x1080 60 FPS Interlaced Broadcast High Definition
1080p Blu-Ray 1920x1080 60 FPS Progressive High Definition
4k UHD 3840×2160 60 FPS Progressive Ultra High Definition
4k DCI 4096×2160 60 FPS Progressive Digital Cinema Initiatives
8k UHD 7680×4320 60 FPS Progressive Ultra High Definition

 

 

Note: There is usually no digital compression of the live data stream data.

  

An RGB color space is any additive color space based on the Red Green Blue color model.  In the digital realm, these colors are determined by 24 bits with each 8-bit byte ranging from 0 to 255 for each of the three primary colors.

  

RGB color space Levels:

· Television - Limited 16-235 for each of the three (red, green, and blue) color levels of 219.

· PC Monitor - Full 0-255 for each of the three (red, green, and blue) colors levels of 256.

 

YCbCr, Y′CbCr, or Y Pb/Cb Pr/Cr, also written as YCBCR or Y′CBCR, is a family of color spaces used as a part of the color image pipeline in video and digital photography systems. Y′ is the luma component and CB and CR are the blue-difference and red-difference chroma components. Y′ (with prime) is distinguished from Y, which is luminance, meaning that light intensity is nonlinearly encoded based on gamma corrected RGB primaries.

  

YCbCr color space levels

· ITU-R BT.601 conversion

· ITU-R BT.709 conversion

· ITU-R BT.2020 conversion

· SMPTE 240M conversion

· JPEG conversion

  

I/O Ports and Configuration

· Inputs

o S Video

o RGB Component

o CVBS Composite

o VGA

o SCART

· Output Resolution HDMI

o 720

o 1080

o 4k

o 8k

· Color Space

o TV Limited 16-235 = total of 219 levels from black to white.

o PC Full 0-255 = total of 256 levels from black to white.

o YCbCr

· Aspect Ratio

o 4x3 Vertical Black Bars

o 16x9 Stretched

o 16x9 Letterbox Horizontal Black Bars

o 16x9 Zoom with loss of top and bottom of 4x3 image and lower resolution.

· Chroma

o Brightness

o Contrast

· Color

o Tint

o Saturation

· Picture

o Sharpness

o Detail

o Noise Reduction

  

 

   An example of a failed expensive converter

 


 

   Black Box AVSC-VIDEO-HDMI

 

The Black Box Component/Composite to HDMI Converter is a $200 device with a number of features that they claim are superior to the $12 CoolDigital HD Video Converter shown earlier.  With assurances from the Black Box support team, I purchased one of these impressive looking devices.  However, after going through every setting, I found none that would allow this box to work with a PC monitor in full color space of 0-255.  Later conversations with Black Box support revealed that this box will only output limited 16-235.

   

There is nothing in the documentation or the datasheet that describes the digital HDMI output.

It seems these over priced devices are no better than the $12 CoolDigital. 

 

This device is designed for televisions with limited Red 16-235, Green 16-235 and Blue 16-235 color space, not industrial or high fidelity monitors with a wider color apace of RGB 0-255.  Why the ATSC decided to go with this color space is - well another stupid Hollywood elite F-up.

 

What is absolutely absurd about Black Box is every device one can purchase including the following I own, have the capability of switching between limited and full. 

  • Blu-Ray: Samsung BD-J5770 - 2015

  • HD-DVD: Toshiba HD-A3 - 2007

  • DVD: Panasonic DVD-5700 - 2018

  • DVD: Philips DVP5990 - 2009

  • DV-Cam: Sony HVR-M25U - 2006

  • HDTV ATSC Tuner: PHD-205 - 2007

   

Note. Each of the above pieces of equipment have their own unique description for this color space option.

    

   

[1] CoolDigital HD Video Converter

To adjust parameters:

A 3-second hold down of the FORMAT button toggles between 16:9 and 4:3 formats.
A press and release of the FORMAT button toggles output resolution between 720P and 1080P.