Video signals are important to understand for: what your equipment can use, what signals are glitchable, and how you can convert between signals.
Analog Luma - A History and Explanation of Video
Intro to Chroma: From RGB to Component Video
https://github.com/oyvindln/vhs-decode/wiki/Acronyms-Guide
https://www.analog.com/en/technical-articles/basics-of-analog-video.html
https://www.analog.com/en/resources/technical-articles/understanding-analog-video-signals.html
https://en.wikipedia.org/wiki/Analog_television#Structure_of_a_video_signal
NTSC Studio Timing Principles and Applications
https://github.com/oyvindln/vhs-decode/wiki/TV-Systems
Cable Television
- Multiple channels are sent down a single wire via Frequency Division Multiplexing (FDM), with channels resigning on frequency bands from 50 MHz to 1 GHz.
- https://en.wikipedia.org/wiki/List_of_common_resolutions#CCTV
- 960H - 960 x 480 (NTSC) or 960 x 576 (PAL)
- HD-TVI - High Definition Transport Video Interface
- HD-CVI - High Definition Coaxial Video Interface
- Analog High Definition
- https://www.securitycameraking.com/securityinfo/tvi-vs-cvi-what-is-the-difference/
- 1000ft of ANALOG HD video over a single cable?! [AHD/CVI/TVI]
- https://ipvm.com/discussions/singmai-electronics-the-real-inventor-of-hd-cvi-and-hd-tvi?page=1#post_59275
- https://www.edn.com/transmitting-hd-video-over-rg-59-cable/
NTSC - National Television Standards Committee
- North America and Japan
- 525 Interlaced lines at 29.97 frames/sec
PAL - Phase Alternate Line
- Europe
- 625 Interlaced lines at 25 frames/sec
SECAM - Sequential Color and Memory
- France, USSR, China, Pakistan
- 625 Interlaced lines at 25 Frames/sec
- Analog
- 3 color RCA jacks (Green, Blue, Red), or BNC.
- Green = Luminance and Sync
- Blue = Pb = Blue minus Luma
- Red = Pr = Red minus LUma
- Aka YPbPr, YCbCr, YUV
- Sync is carried on the Y (luminance) channel.
- Analog
- Yellow RCA cable or BNC connector.
- Can be easily glitched and easily sent to CRT TVs
- Most glitch boxes/devices use composite for both input and output signals (through RCA connections)
- Aka CVBS (Composite Video Baseband Signal)
- Digital
- Not useful for glitching
- This protocol has become very popular and is the underlying protocol used in USB-C connectors; as well as Thunderbolt3 and 4.
- https://en.wikipedia.org/wiki/Digital_Visual_Interface
- Digital and analog
- Successor to VGA; and certain modes may have backwards VGA compatibility.
- Digital
- Difficult to glitch because of digital internal correction, but some devices can
- Can be converted to composite with a cheap HDMI-to-composite converter
- Can be used for feeding certain video devices that take an HDMI input
- Can be used for upscaling/downscaling a video signal
- Designed to be compatible with Eurorack CV signals. However, while Eurorack typically operate at -5v to +5v (10v peak-to-peak); LZX is typically 0-1v, with some bi-poloar modules being -1v to +1v. 0-1v is clever because 0 is full black, and 1v is full white. This makes dealing with multipliers and dividers straightforward.
- ESG3 - Encoder and Sync Generator Module.
- TBC2 - Dual Video Input Module
- LZX Industries Presents: The Patchable Video Standard - Section 1 (Intro)
- https://docs.lzxindustries.net/docs/guides/standards
- HomeGrown Visuals Video Synth Playlist - https://www.youtube.com/playlist?list=PLkGLuhLWJUdnJJXBbRAdWnNuY7rHDpWW0
- Analog
- Mostly deprecated with the Over The Air (OTA) to Digital
- VHF - Very High Frequency - Channels 1-13
- UHF - Ultra High Frequency - Channels 14-83
- RF to Composite modulator adapters are commonly available. You likely won’t need to do the reverse (convert RF to composite)
- Originally just wires connected to “rabbit ear antennas”
- Often found on older televisions, VCRs, older video game consoles, and certain types of video modulators. Signals are encoded in channels, such as channel 3 or 4.
- Low image quality
- Analog
- Red, Green, Blue transmitted as individual colors.
- https://www.retrorgb.com/rgbadvanced.html
- TVs can be modded to accept RGB input. https://sector.sunthar.com/guides/crt-rgb-mod/rgb-theory.html
- https://www.retrorgb.com/sync.html
- RGBs - 4 lines, Horizontal and Vertical sync on 1 line.
- RGBHV - 5 lines, Horizontal and Vertical sync separate lines. (You can think of this as VGA, although VGA refers to a specific resolution.) Note the HV is 5v.
- RGsB - 3 lines; with Horizontal and Vertical sync sharing the Green line. Rare.
- https://en.wikipedia.org/wiki/Component_video#RGB_analog_component_video
- Digital (but had 4fsc sampled analog direct in older provisions for D2/D3 tape)
- https://en.wikipedia.org/wiki/Serial_digital_interface
- Transmits uncompressed digital video signals over coaxial cables, allowing for very high quality video without degradation even over long cable runs
- Commonly used in professional broadcasting, video production, and other applications where high-quality, reliable, and uncompressed digital video transmission is essential
- Professional cameras
- Video mixers/switchers/routers
- Video capture cards/digital video recorders
- Monitoring & display equipment
- While SDI is widely used in professional settings, HDMI is the standard for consumer audiovisual equipment due to its versatility and support for both video and audio in a single cable.
SD-SDI
480i, 576i
ED-SDI
480p, 576p
HD-SDI
720p, 1080i
Dual Link HD-SDI
1080p60
3G-SDI
1080p60
6G-SDI
1080p120, 2160p30
12G-SDI
2160p60
24G-SDI
2160p120, 4320p30
- https://en.wikipedia.org/wiki/S-Video
- 4 Pin connector (in consumer gear)
- Y (Luminance along with Hsync and Vsync),
- C (Chrominance) + Color Burst subcarrier timing reference
- Ground
- Ground
- Can also be found as 2 BNC connectors
- Y (Luminance along with Hsync and Vsync),
- C (Chrominance) + Color Burst subcarrier timing reference
- With the 2 BNC connectors barrel’s serving as grounds
- Analog
- ?Can this signal be glitched?
- Some video mixers and devices (DVD players, CRT TVs, video enhancer, etc.) have S-Video inputs/outputs
- S-Video provides a clearer and sharper image compared to composite video because it keeps luminance and chrominance separate
- https://en.wikipedia.org/wiki/Vga
- Analog
- Glitchable, see CHA/V
- Can be converted to composite with a VGA-to-AV converter
- Often found in older computer monitors, projectors, and displays, as well as video mixers
- How VGA Works
- http://javiervalcarce.eu/html/vga-signal-format-timming-specs-en.html