BitJazz
SheerVideo Power
Y'CbCr 8bv 4:2:2p Data

The following table shows the compression statistics for the Sheer Y'CbCr 8bv 4:2:2p codec for each of the Kodak images. When encoding Y'CbCr 8bv 4:2:2p images with the Sheer Y'CbCr 8bv 4:2:2p codec, SheerVideo's compression power ranges from 1.81 in image 13 to 2.82 in image 03, averaging 2.43. The space savings for Sheer Y'CbCr 8bv 4:2:2p ranges from 45% to 65%, averaging around 58%.

		uncom- pressed	Sheer- Video
#	image	'2vuy' 'yuvs'	'Shr3'
01		786432 1.00 0%	363269 2.16 54%	bytes power space savings
02		786432 1.00 0%	306949 2.56 61%	bytes power space savings
03		786432 1.00 0%	279074 2.82 65%	bytes power space savings
04		786432 1.00 0%	312401 2.52 60%	bytes power space savings
05		786432 1.00 0%	385755 2.04 51%	bytes power space savings
06		786432 1.00 0%	341897 2.30 57%	bytes power space savings
07		786432 1.00 0%	291969 2.69 63%	bytes power space savings
08		786432 1.00 0%	389398 2.02 50%	bytes power space savings
09		786432 1.00 0%	293571 2.68 63%	bytes power space savings
10		786432 1.00 0%	295243 2.66 62%	bytes power space savings
11		786432 1.00 0%	322116 2.44 59%	bytes power space savings
12		786432 1.00 0%	284596 2.76 64%	bytes power space savings
13		786432 1.00 0%	435295 1.81 45%	bytes power space savings
14		786432 1.00 0%	359854 2.19 54%	bytes power space savings
15		786432 1.00 0%	304018 2.59 61%	bytes power space savings
16		786432 1.00 0%	299160 2.63 62%	bytes power space savings
17		786432 1.00 0%	298710 2.63 62%	bytes power space savings
18		786432 1.00 0%	376413 2.09 52%	bytes power space savings
19		786432 1.00 0%	330019 2.38 58%	bytes power space savings
20		786432 1.00 0%	302715 2.60 62%	bytes power space savings
21		786432 1.00 0%	337114 2.33 57%	bytes power space savings
22		786432 1.00 0%	338446 2.32 57%	bytes power space savings
23		786432 1.00 0%	280119 2.81 64%	bytes power space savings
24		786432 1.00 0%	353707 2.22 55%	bytes power space savings
Mean		786432 1.00 0%	328409 2.43 58%	bytes power space savings

The Y'C_BC_R 8bv 4:2:2 format, found in the pixel format '2vuy', is the most common uncompressed video format today. Y'C_BC_R 8bv 4:2:2 contains only two 8-bit values per pixel. While luma (Y') is represented at every pixel, each pixel only retains a single chroma value, alternating between C_B and C_R.

Y': luma CB: blue-yellow chroma

Y': luma CR: red-cyan chroma

Y'C_BC_R 8bv 4:2:2, the luma component has a nominal range of 220 unsigned integer values, and both chroma components have nominal ranges of 225 offset binary integer values. The chroma range of [16..240]->[-1/2..1/2] allows some play on both ends for out-of-range colors. Likewise, the luma component's [16..235]->[0..1] range leaves footroom at the bottom for subblack colors as well as headroom at the top for superwhite colors. This format is compliant with the International Telecommunication Union's Recommendation BT.601-4, and is used in standard uncompressed Y'C_BC_R 4:2:2 digital video tape (SMPTE D-1), standard uncompressed digital video links (SMPTE 259M), and professional video equipment.

At the time we performed these tests, there was no uncompressed Y'C_BC_R 8bv 4:2:2 QuickTime codec available. So we wrote our own QuickTime codec to translate between yuv2 and 2vuy, using the simple standard equations given in Recommendation ITU-R BT.601-4:

Y' = floor(y' x 219 / 255 + 16.5)
C_b = floor(c_b x 224 / 254 + 128.5)
C_r = floor(c_r x 224 / 254 + 128.5)

The Sheer Y'CbCr 8bv 4:2:2 encoder was used with the settings: Millions of Colors, Progressive.

With only 2 byte-size components per pixel, the uncompressed size of each these Y'C_BC_R 8bw 4:2:2 frames is 2 x 768 x 512 = 786432 bytes.