Kamera

Amatör Video Formatları

The cells that are left totally empty are ones for which I don't know the for answers yet. If you know the answers, please tell me. the order of the video systems are in approximate quality order, from the best to the worst (from my subjective point of view).

Video
P DVC	N DVD DD	P Ld	N Ld DD / PCM	P Bcast	N Bcast	P SVHS	P Hi-8	P Beta	P VHS	N VHS	P V8	CD-I
Domain	Digital	Digital	Analog	Analog	Analog	Analog	Analog	Analog	Analog	Analog	Analog	Analog	Digital
Compression	5:1	60:1	Comp	Comp	Comp	Comp	Y/C	Y/C	Y/C	Y/C	Y/C	Y/C	40:1
Luminance Horiz. Res.	500	500	450	420	400	330	400	400	250	240	240	230	240
Luminance Vert. Res.	576	480	576	480	576	480	576	576	576	576	480	576	280
Luminance S/N Ratio	54	48		52	55	55	46	45	43	43		45	48
Chroma Horiz. Res.	250	250	100	70	100	70	40	40	45	40	40	40	120
Chroma Vert. Res.	200	240	200	480	200	480	140	140	200	140	160	140	140
Chroma S/N Ratio	54	48											48
Frames/s	25	30/24	25	30	25	30	25	25	25	25	30	25	25
Interlace	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No
Compr. Artifacts	Minimal	Minor / Some	Dot crawl	Dot crawl	Dot crawl	Dot crawl	No	No	No	No	No	No	Severe

Audio Columns

Video
P DVC		N DVD DD	P Ld	N Ld DD	N Ld PCM	P Bcast	N Bcast	P SVHS	P Hi-8		P Beta	P VHS	N VHS	P V8	CD-I
Domain	Digital		Digital	Digital	Digital	Digital	Digital	Analog	Analog	Digital	Analog	Analog	Analog	Analog	Digital	Digital
Compression	No	N-lin	10:1	No	10:1	No	14:10	-	DBX	N-lin.			DBX	DBX	N-lin.	5:1
Sampling Bits	16	12	18..20	16	18..20	16	14	-	-	8	-	-	-	-	8	16
Sample Rate	48000	32000	48000	44100	48000	44056	32000	-	-	32000	-	-	-	-	32000
S/N Ratio	96	90	90	96	90	96	84	65	90	85	65	90	90	90	85	96
Low Frequency	5	5	5, 2	5	5, 2	5	5	60	20	20	30	20	20	20	20	20
High Frequency	22k	15k	20k, 120	20k	20k, 120	20k	15k	15k	20k	15k	14k	20k	20k	20k	15k	20k
Channels (+low quality)	2	4	n x 5.1	2	5.1 (+2) (+1)	2 (+2)	2 (+1)	2 (+1)	2 (+2)	2	2 (+1)	2 (+1)	2 (+1)	2 (+2)	2	2

P DVC: PAL Digital Video Cassette
DVD: Digital Video Disc
P Ld: PAL Laserdisc
N Ld DD: NTSC Laserdisc with 5.1 track Dolby Digital (AC-3) audio
N Ld PCM: NTSC Laserdisc with conventional digital PCM audio
P Bcast: PAL Broadcast
N Bcast: NTSC Broadcast
P SVHS: PAL Super-VHS
P Hi-8: PAL Hi-8
P Beta: PAL Beta
P VHS: PAL VHS
N VHS: NTSC VHS
P V8: Pal Video-8. Notice, that digital sound is not typical of consumer models. See Hi-8 columns for info on analog sound.
CD-I: Philips CD-I or MPEG-1

Rows
Video
Domain: Is the video signal in the digital or analog domain?
Compression: If digital, how much is the video signal compressed? If analog, in which way is the signal stored?
Comp: Composite video. It is the responsibility of the receiver to recover the luminance and chrominance part of the signal.
Y/C: Separate video. the luminance and chrominance parts of the picture are stored separately in the video stream. thus they may also be sent to the receiver separately. (this is however often not the case. For instance, I've yet to see a consumer VHS deck with Y/C outputs.)
Luminance Horiz. Res.: Luminance horizontal resolution (lines)
Luminance Vert. Res.: Luminance vertical resolution (lines)
Luminance S/N Ratio: Luminance signal-to-noise ratio (dB)
Chroma Horiz. Res.: Chrominance horizontal resolution (lines)
Chroma Vert. Res.: Chrominance vertical resolution (lines)
Chroma S/N Ratio: Chrominance signal-to-noise ratio (dB)
Frames/s: Maximum amount of full, different frames/second (f/s)
Interlace: Is the image displayed in an interlaced fashion?
Compression Artifacts: If the image is compressed, does the compression produce visible artifacts? (dot crawl is what happens when a TV set can't separate luminance from chrominance properly.)

Audio
Domain: Is the audio signal in the digital or analog domain?
Compression: If digital, how much is the sound compressed? If analog, what companding method is used?
Sampling Bits: If digital, the amount of bits used in sampling before compression
Sample Rate: If digital, the sampling rate (samples / s)
S/N Ratio: the signal to noise ratio of sound with noise reduction (dB)
Low Frequency: the lowest frequency the system can reproduce without attenuating more than 3 dB (Hz)
High Frequency: the highest frequency the system can reproduce without attenuating more than 3 dB (Hz)
Channels (+low quality): Channels that can be used. In parenthesis are the analog channels of NTSC laserdiscs and linear tracks of VHS video.

Calculating Horizontal Resolution

Although calculating vertical resolution is simple (the amount of horizontal scanlines), horizontal resolution is a little trickier thing.

In video industry, horizontal resolution is given as if the video screen was as wide as it is tall. this way, if a video device has the same horizontal and vertical resolution, it can be thought of having "square pixels". If you want to know how many vertical lines the device actually can display, (for the whole width of the screen, that is), you have to multiply the given resolution with 4/3, which is the aspect ratio for normal display devices.

For instance, if you have a Amiga computer that can display graphics (in low-res interlace mode) at a computer resolution of 368x564, the video resolution is 3683/4 x 564 = 276 x 564, which is little better than VHS. the other way around: If you have an NTSC LD player, that has a horizontal resolution of 420 lines, you can actually have 4204/3 = 560 vertical lines, or horizontal pixels, on your TV screen.

this is why, for instance, the given horizontal luminance resolution of CD-I is not given as 320, but 240 (320 * 3/4). the number would be even less if proper low-pass filtering was used, but in CD-I, nothing is done to prevent pixels from showing out.

On the other hand, the theoretical resolution of DVD would be 540 video lines with my calculations. However, since the signal is low-pass filtered (just as it should be), little less than 10% (40 lines) is lost in the process.