Video Formats – Standard Definition (SD)
• SONY
ITMA 12 – Betacam SX (1996)
– Betacam SP (1987)
Digital Video – Digital Betacam (1993)
• Panasonic
– DVCPro-50
Krates Ng
Fall 2008
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Video formats – DV Video formats – High Definition (HD)
• Mini DV • Pro-sumer/semi-professional grade
• DVCAM from Sony – HDV from Sony and JVC
• DVC Pro25 from JVC and Panasonic – DVCPro – HD
• My favorite:
– Sony PD170P, Panasonic AG-DVX-100A
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Video formats – High Definition (HD) HD VTRs
• Broadcast grade
– Sony HDCAM (1997)
– Sony HDCAM-SR (2003)
– DVCPro-HD from Panasonic Sony HDW-F500 Sony SRW-5000
US$72100.00 List price
– D5 from Panasonic
Panasonic AJ-HD3700B
HD 10-bit 4:2:2
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Tapeless video camera HD and SD Hybrid
• Hard disk based • 3MOS
• JVC Everio series • 1920x1080 25p
• AVCHD compression
• MPEG-2
• 17Mbps/VRB,
• 720x480 60i (N) 13Mbps/VBR,
• 8.5Mbps, 5.5Mbps, 9Mbps/VBR, 6Mbps/VBR
4.2Mbps (VBR), • List HK$9280.00 (Dec08)
1.5Mbps (VBR)
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Watch these new cameras! Image size
• Video resolution mostly = 72dpi
• Panasonic AG-HVX200 (Dec 05) • SD
– NTSC: 720 × 486
• 1/3” 3-CCD – PAL: 720 × 576
• DVD or DV
• 16:9 / 4:3 – NTSC: 720 × 480
– PAL: 720 × 576
• DVCPro-HD/DVCPro-50/DVCPro/DV • HDV
• Variable frame rates – 1080/50i/60i: 1440 × 1080
– 720/25p/50p/30p/60p: 1280 × 720
• Solid-state storage • HD
– 18 different scan rates, i=interlace, p=progressive
• List US$6,600 (w. 4GB card) – 480i or 480p : 720 × 480
– 720i or 720p : 1280 × 720
• www.panasonic.com/p2
– 1080i or 1080p : 1920 × 1080
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Tape format Date rates
• VHS/ S-VHS (1987): Analog, universal, poor quality
• DV
• In general, higher data rate = greater quality
– JVC DVCPro-25 • CD Audio (44KHz, 16 bits) = 176KB/sec.
– Sony DVCAM
– Mini DV • DV=3.75MB/sec.
• DVCPro-50
• DVCPro-HD (100) • SD uncompressed 8-bit = 20.2MB/sec.
• HDV • SD uncompressed 10-bit = 26.7MB/sec.
• Sony Betacam SX (digital), Betacam SP (analog), Digital
Betacam (digital betacam)
• D1, D5
• HDCAM, HDCAM-SR
• HDV 720p=2.4MB/s, 1080i = 3.2MB/s
• HD uncompressed 1080i = 160MB/s!!!!!!
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Data storage RAID
• 1 hour DV needs 13GB (PAL or NTSC) • Redundant Arrays of Inexpensive Disks.
• 1 hour of HDV 720p = 8.7GB
• Developed in the late 1980’s and early
• 1 hour of HDV 1080i = 11.5GB
1990’s.
• 1 hr. SD uncompressed 8-bit = 72.7GB
• 1 hr. SD uncompressed 10-bit = 96GB • Classified into many levels, e.g. RAID 0,
• 1 hr. of HD 1080i = 560GB!!!! RAID 1, RAID 5…etc.
• Most hard disks can take data at 20-50MB/sec • Performance (throughput), storage
• How do you meet the data rates and storage capacity, redundancy and costs.
requirements for video works?!
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RAID 0 RAID 1
• Striping: spread the data across different drives.
• Does not provide any data redundancy but gain • Disk mirroring.
performance.
• If one drive fails, all the data is damaged.
• Used often in low-cost video applications.
from http://www.finitesystems.com/PRODUCT/raid/raidlevel.htm
from http://www.finitesystems.com/PRODUCT/raid/raidlevel.htm
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RAID 5 Color sampling
• Data is striped across disk drives. • A form of compression to reduce chroma
• Parity is used to correct errors and is striped components since our vision cannot see the fine
color details.
across disk drives.
• Common sampling formats:
• When one drive fails, all data is still available. – Uncompressed: 4:4:4
– Digital Betacam: 4:2:2
– Betacam SP: around 4:1:1 – 4:2:2
– DV: 4:1:1 (NTSC), 4:2:0 (PAL)
– DVD: 4:2:0
– HD: 4:4:4 (digital cinema), 4:2:2 (broadcast)
– HDV: 4:2:0
from http://www.finitesystems.com/PRODUCT/raid/raidlevel.htm
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YCbCr Color sampling – 4:4:4
• Similar to YUV
• ITU-R BT.601 recommends:
– Y = 0.299R + 0.587G + 0.114B
– Cb = (B – Y) / 1.772
– Cr = (R – Y) / 1.402
Diagram from www.larryjordan.biz
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Color sampling – 4:2:2 Color sampling – 4:1:1
Diagram from www.larryjordan.biz
Diagram from www.larryjordan.biz
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Color sampling – 4:2:0 Which color sampling is good for you?
• In general, you cannot choose the
sampling method because it is pre-set.
• Go for the highest affordable video format.
• If involves a lot of digital post-production
work, e.g. chroma keying, compositing,
color correction, computer-generated
imaging, must use the highest.
Diagram from www.larryjordan.biz
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Time code Pixel aspect ratio
• A label to identify each frame of video. • Computer:
• Format – 1:1 (square pixel)
– HH:MM:SS:FF • NTSC
– HH = Hours – 1 (H) : 0.906 (W)
– MM = Minutes • PAL
– SS = Seconds – 1 (H) : 1.06 (W)
– FF = Frame count • HD
– e.g. 01:23:15:08 – 1:1 (square pixel)
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Pixel aspect ratio – creating computer graphics Interlace/Progressive – creating computer graphics
• To compensating rectangular pixels. • Must be thicker to avoid flickering and
• PAL
– 4:3 720×576
changes in dimension, width, or position.
– Tiff at 4:3 768×576, 16:9 1024×576 • Typefaces 24 points min.
• DV NTSC
– 4:3 720×480
• Lines 4 pixels wide min.
– Tiff at 4:3 720×540, 16:9 853×480 • Avoid lines leaning close to horizontal or
• SD NTSC vertical
– 4:3 720×486
– Tiff at 4:3 720×547, 16:9 853×486 • Avoid fancy fonts with little curves or small
• Check your editing software. lines.
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Margins White
• Action Safe • DV
5%
– Contains all essential 10%
– Black = 0, White = 109%
5% Action safe
action
– 5% in from all edges
• For broadcast or analog, White cannot >
Title Safe 10%
100%.
• Title Safe
– Contains all text and • Computer graphics may be too ‘White’.
essential logos • Set to 92% or lower in Photoshop.
– 10% in from all
edges
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Video Compression – Redundancies GOP-based video compression
• Inter-pixel/Spatial Redundancy • Frame-based and GOP-based
– Neighboring pixels are highly correlated. • Group of picture
• I-frame starts the GOP
• Inter-frame/Temporal Redundancy
• B-frames and P-frames describe the changes to
– Differences between consecutive frames is the previous frame in the current frame.
small. • I BB P BB P BB P BB P BB
• Visual Redundancy • DVD: 15 image GOP, 200KB/sec
– Less sensitive to color. • Digital Betacam: frame based, 27MB/sec
• HDV uses MPEG-2 TS (GOP compression)
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diagram from www.cs.unc.edu/~jeffay/comp249f99
diagram from www.cs.unc.edu/~jeffay/comp249f99
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Codecs (coding and decoding) Movie Maker 2 Tutorials
• Too many of them, e.g. Windows Media, • www.atomiclearning.com/moviemaker2
Real, Quicktime, Divx…etc. • www.amherst.edu/it/software/moviemaker/movie
• Comparing: maker.pdf
– Compression ratio (file size) • www.microsoft.com/windowsxp/using/moviemak
– Quality er/videos/create.mspx
– Lossy/lossless • www.ischool.utexas.edu/technology/tutorials/gra
– Bit rate phics/moviemaker2
– Time (encoding/decoding)
• Check out www.free-codecs.com
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