What is the deal with digital and analog signals in video? (cables)?

Question

I have a camera that has an HDMI output. This is digital, correct? so I can't have an HDMI to VGA cord (analog). But I can have an HDMI to DVI cord, both digital. But I have seen DVI to VGA adapters! why do these work?

Short story is, I am trying to hook my camera to a monitor (VGA) In the cheapest way possible. The camera is a Canon 60D DSLR camera, so it has mini HDMI and maybe some other possible outputs. What do I buy?

I would also appreciate an explanation of the Digital and Analog stuff to, for future reference.
(VGA, DVI, HDMI, RCA, BNC, S-Video, Composite vs component, etc)

THANKS SO MUCH

Answer 1

An analog signal is basically a variation in voltage sent over an electrical line that produces or mimics a wave form while digital sends a binary code over optical or electrical line, basically dots and dashes... Digital code needs a converter to interpret the binary code and then transfer that in to a wave form variation readable by the TV screen or computer, there is lots of information send for video on both analog and digital formats color temperature pixel count refrech rate changes in white levels etc...the advantage of digital is this information can be kept cleaner because of the way its written; with out mixing with the other codes...also its faster meaning more information can be sent in a shorter period of time....... analog has a harder time distinguishing one type of wave form from another...composite send the entire analog video signal over one line leaving the analog circuity to break it apart and figure it out...component breaks the signal down into 3 different color spectrum and lines sending that over three lines, which helps to keep information separate and also three lines just means more information can be sent faster ...but its still analog; although there is some componet digital available also....DVI is basic digital designed originally for Computers HDMI is DVI plus sound plus copy rights protection; major studios were unwilling to release there copy right material unless some kind of copy rights protection was built into the system....

Answer 2

An analog signal represents color information with voltages on a cable, one pixel at a time. The information chosen for each format is slightly different, but the quality of a particular format is usually better if it has more channels(wires) to work with. Composite video is the worst because it includes all the color and sync information in one signal. S-video is split composite, only slightly better. Component has three channels and is a significant improvement with support for higher resolution. VGA is the best because it has a separate signal for red, green, blue, and the two timings.



A digital video signal is very similar to Morse code. It uses a series of high and low voltages on a cable to represent numbers, which are then used to set the color of each pixel. They are more robust because a weak signal still produces the right numbers, and a perfect picture, as long as the high and low bits can be discerned.



To your other questions, HDMI and DVI both use the same standard digital signal. The differences are that HDMI includes digital audio, and the DVI connector has a separate analog option.

http://upload.wikimedia.org/wikipedia/commons/0/03/DVI_pinout.png

The salmon-corored pins to the right are an optional built-in VGA cable that carries the same red/green/blue analog signal. Below are the combinations and labels.

http://commons.wikimedia.org/wiki/File:DVI_Connector_Types.svg



So yes, you do need an active device to get from hdmi to vga, but it's not that expensive

http://www.amazon.com/Cable-Matters-Active-Adapter-Charging/dp/B00879DM56/

http://www.amazon.com/Cable-Matters-Plated-Female-Adapter/dp/B004PW1XRS/

Or if you need sound

http://www.amazon.com/HDMI-VGA-converter-Audio-Converter/dp/B003O55U8K/



Lastly, RCA and BNC are just connector types. They usually used for analog signals, but not always.

Answer 3

Simply DVI in its fullest configuration has DVI-Digital (very similar to HDMI), and basically VGA, on one largish plug. The VGA video and DVI-Digital are on different pins of the connector, except share some control leads.

A DVI to VGA adapter or cable connects just the VGA and control pins, a DVI to HDMI adapter the digital video and control pins to the HDMI plug. So there, you cannot convert HDMI to VGA using DVI plug adapters as an intermediary because the digital and analog video are on different pins, the signals still strictly separate.



As for the descriptions:

VGA is analog computer graphics. It has discrete R/G/B video leads with separate sync pulses, and DDI lines to tell the computer display capabilities.

DVI-D is bascally the same, except is digital, and uses differential signalling, and as well has a signal clock. DVI has a dual link version that has an extra set of RGB signal lines, for extra color depth or resolution. As said above, DVI-I is a combo connector with DVI-D and VGA.

HDMI is basically DVI-D only on a smaller connector, with differential SPDIF audio added, and CEC.



RCA and BNC are simply types of single circuit plugs. RCA is used for consumer A/V, BNC for commercial video and RF.



Composite is a video signal that has a luma (sum of R, G, and B video, called Y), and chroma. (red-Y and blue-Y modulated on a carrier).

S-video is the same video signal, but have the Y and C signals on separate lines. That allows more bandwidth and no cross interference for each, meaning an improved picture. It is still hobbled by the bandwidth and frequencies of the carrier.

Component takes that one step further, having each color difference signal have its own line.

That improves bandwith and allows high resolution.

For analog consumer A/V, they all use RCA plugs for the video and stereo audio, except S-video, which typically uses a 4 pin mini-din for picture, RCA for sound. The standard for Toslink is a squarish plug, but some equipment use a likeness of a 3.5mm plug.



To add is digital audio. On consumer equipment, that uses a standard called SPDIF, and uses an RCA plug/cord the same as video. Optical audio is called TOSLINK, which basically is SPDIF with a light emitter and receiver, which connect with a fiber optic cable.

Answer 4

- Camera says it should have a mini hdmi type c output and usb 2.0, and you said monitor only has vga input.

= Hdmi to vga converter. You will need a mini hdmi type c to hdmi cable and a vga cable at least. Converter should come with a power cord and maybe comes with it's own hdmi and/or vga cable. Should do up to 1920x1080p (16:9) and also see if you can find one with audio outputs for audio. (Don't get a vga to hdmi converter, that's the wrong direction).

OR

= Usb 2.0 to vga adapter. Usb sides goes into output device and other side needs a vga cable. You don't need a power cable since output device does that, may come with it's own vga cable. Should do up to 1920x1080p (16:9) and also see if you can one with audio outputs for audio. (Don't get a vga to usb 2.0 adapter, that's the wrong direction).



- DVI-D is digital, DVI-A is analog, DVI-I is both analog and digital. - DVI-D can only go into DVI-D or DVI-I. - DVI-A can only go into DVI-A or DVI-I. - Unlikely to find one of these, but DVI-I can only go into DVI-I. - Single-link can go into both single-link and dual-link, dual-link can only go into dual-link.



If your monitor/tv had a different port than vga, here is your other options with best possible video/audio qualities below.



For video cables from best to least:

- HDMI cable: Standard speed is capable of up to 1280x720p/8-24bpp/60hz or 1920x1080i/8-24bpp/60hz. High speed is capable of up to 4096×2160p/36bpp/24hz or 1920×1200p/48bpp/60hz.

- Displayport cable: is capable of up to 2560×1600p/30bpp/60hz (hdmi can do that too btw), I think it is capable of up to 4096×2160p/36bpp/24hz or 1920×1200p/48bpp/60hz too.

- DVI cable: Single-Link is capable of up to 1920x1200p/24bpp/60hz or 3840x2400p/24bpp/17hz. Dual-Link is capable of up to 2560x1600p/24-48bpp/60hz or 3840x2400p/24-48bpp/33hz.

- VGA cable: is capable of up to 2048×1536p/24-32bpp/85hz or 2560x1024p/24-32bpp/85hz or 2800x1050p/24-32bpp/60hz or 3200x1200p/16bpp/85hz.

- Component-video cable: is capable of up to 1280x720p/8-24bpp/60hz or 1920x1080i/8-24bpp/60hz.

- Scart > (S)eparate-video > Composite-video cables: is capable of up to 720x480i/8-24bpp/60hz NTSC or 720x576i/8-24bpp/50hz PAL (no progressive scan btw, PAL > NTSC).

- (Hdmi, displayport, dvi is digital video), (Dvi, vga, component, scart, s-video, composite is analog video).



For audio cables: From best to least:

- HDMI or Displayport cables: is capable of up to 8 channels of audio and up to 24-bit-depth with up to 192,000hz sample rate at the lossless/hd compression surround sound formats.

- S/PDIF coaxial or s/pdif optical cables: is capable of up to 6 channels of audio and up to 20-bit-depth (16 or 24 optional) with up to 48,000hz sample rate at the lossy/non-hd compression surround sound formats.

- Scart or RCA R/W composite audio cables: is capable of up to 2 channels of audio and analog has maximum audio quality. RCA G/B/G/B/T/P for other channels.

- (Hdmi, displayport, s/pdif coaxial, s/pdif optical is digital audio), (scart or rca r/w or headphone jack is analog audio).



Other cables:

- Displayport to either hdmi/dvi/vga adapter cable (displayport side is male, hdmi/dvi/vga side is female = works only one way)&(dp to hdmi only has audio).

- Dvi-d single-link to hdmi cable or Dvi-a single-link to vga cable (both cables work either way)&(both cables do not carry audio).

- RCA red/white to 2.5/3.5.ect headphone jack cable (cable works both ways, only carries analog audio), (do not confuse this with a mini optical, that's digital and only works with digital for optical cables).

- USB (1.0, 2.0, 3.0 .ect) to either hdmi/dvi/vga adapter cable (usb side is male, hdmi/dvi/vga side is female = works only one way)&(usb to hdmi only has audio).