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Duration of Legal Information Minimum Text Height Supers in Commercial Colour encoding systems for 5 words per second (0.2 seconds SD 4:3 Text Safe SD 4:3 analogue TV. per word or 300 words p...

Duration of Legal Information Minimum Text Height Supers in Commercial Colour encoding systems for 5 words per second (0.2 seconds SD 4:3 Text Safe SD 4:3 analogue TV. per word or 300 words per minute). Minimum Text Height = 14 lines 67.5% Width SD When placed on a single background = 12 lines 90% Height Interlaced 9 words or fewer = 0.2 seconds Composite video per word + 2 seconds added SD 16:9 Text Safe HD 16:9 10 words or more = 0.2 seconds Minimum Text Height = 16 lines 90% Width PAL – Phase Alternate Line per word + 3 seconds When placed on a single background = 14 lines 90% Height Automatic Colour Correction EXAMPLES: HD 16:9 Action safe area = 80% 720x576 1 word (0.2x1+2) = 2.2 seconds Minimum Text Height = 30 lines Title safe area = 90% 25fps (50 fields) 5 words = 3 seconds When placed on a single background = 26 lines 50Hz 9 words = 3.8 seconds 625 lines of resolution with 576 10 words = 5 seconds carrying visible image. Aspect ratios 20 words = 7 seconds Resolution Type Name Aspect Ratio Pixel Size NTSC – National Television Superimposed text on 2 lines or SD 480p 4:3 OR 1.33:1 640 x 480 Standards Committee more = 0.25 seconds per word + 3 HD 720p 16:9 OR 1.78:1 1280 x 720 Manual Tint Control seconds Full HD 1080p 16:9 OR 1.78:1 1920 x 1080 Abbreviations count as one word. QHD (Quad HD) 1440p 16:9 2560 x 1440 720x480 (486) Postcodes count as two words. 2K video 1080p 1:1:77 OR 1.85:1 2048 x 1080 OR 29.97 (30) fps (60 fields) 1988 x 1080 480 Tech Specs 4K video or UHD 4K OR 2160p 1:1:9 OR 2.35:1 3840 x 2160 525 lines of resolution with 480 Title Safety = EBU R.95-1 8K video or Full UHD 8K OR 4320p 16:9 7680 x 4320 carrying visible image. Sound = R.128 PSE = Ofcom Metadata = Information that describes other data. SECAM – Sequential Colour HD image = EBU tech 2399 Codec = A method for compressing and decompressing data = Make smaller. and Memory Wrapper = File format that holds v/a and other data together in a single file. SECAM is based off PAL Colour Space – ITU BT. R. Rec. 601 = SD AS-11 DPP Bitrates 720x576 Rec. 709 = HD Resolution = 1920x1080 Mb = Megabits 25fps (50 fields) Rec. 2020 = UHD Aspect ratio = 16:9 MB = Megabytes 50hZ Rec. 2100 = HDR Frame rate = 25fps (50 fields)1080i/25; Top field first K = Kilo 625 lines of resolution with 576 DCI-P3 = 4K Colour sampling = 4:2:2 M = Mega carrying visible image. Colour Space = ITU R BT.709 G = Giga Frame Rate Video bit-depth = 10-bit T = Tera Not compatible with PAL – Will 25fps = UK Video = AVC Intra Class 100. 113Mbps. P = Peta replay in Black and White 29.97fps (30) = USA Audio = PCM. 48kHz, 24bits 8 bits in a byte 23.97fps (40) = Film Synopsis = 250-word count 8MBs = 64 Mbs RAID = Redundant Array of Inexpensive Disks PSE RAID Description Disks Fault Tolerance PSE is tested using Harding FPA Systems. RAID 0 - Fast but not protected. Data is spread across 2 None – If one fails = cd.m-2 (candelas per square metre) Striped both disks. all data lost RAID 1 - Data is copied on more than one disk. 2 YES Triggers: Mirrored Protected but only offers half the storage. Opposing changes in luminance of 20cd.m-2 or RAID 2 - 3 YES more. RAID 3 - 3 YES Dark screen luminance below 160cd.m-2. RAID 5 – Data is spread across multiple disks with 3 YES = Parity rebuilds Saturated red luminance. Striping parity. data lost. Sequence of flashes with parity Parity = spread equally across disks but is the Only 1 disk can fail o Occupies more than ¼ of screen equivalent of an entire disk lost (storage wise). at a time, or all data o More than 3 flashes within any one- E.g. 3 disk arrays = 2 are actual data, 1 is parity. is lost. second period. Parity = Reduces the collective amount of data Rapidly changing image sequences (e.g. fast that can be stored in this array. cuts) RAID 6 – Data is spread across all disks with parity. 4 YES = Parity rebuilds Regular patterns = Stripes (parallel, radial, Striping Parity is spread twice = 2 disks lost (storage data lost. curved or straight). 5 or more stripes. with wise). Can handle 2 disks o If stripes change direction, oscillate, double E.g. 4 disk arrays = 2 are actual data, other 2 failing at the same flash or reverse in contrast and pattern parity are parity. time = Double parity. occupies more than 25% of screen area Write time is less than read. o The stripes are still but pattern occupies RAID 10 – 2 disks are mirrored using RAID 1 then both 4 YES = Can only more than 40% of screen area. RAID 0 & 1 sets of 2 disks are striped using RAID 0. handle 1 drive failing o Darker bars in pattern are below 160cd.m-2 combined Only offers half the physical drive capacity but in a mirrored pair. and differs from lighter bars by 20cd.m-2 or fast and safe. Data loss if 2 disks more. E.g. 4 disks = only use 2 for actual storage. in same pair fail at Fault tolerance of 1 and speed of 0. same time. 9 frames = resets the count File Systems Transcoding = Converting the codec Compatibility File Size Partition Size to another codec to meet specific FAT 32 – File Allocation Most Compatible – Windows, Macs & Linux 4GM Limit 2TB Limit requirements. Table Encoding = Converting raw data into exFAT – Extended FAT = Fully compatible with Windows and modern devices. Unlimited Unlimited a specific format/ codec. Made as an Not as compatible with older devices & Linux. Decoding = Converting encoded data improvement of FAT32. back into a format that can be played NTFS – New Technology Default file system is Windows = Only fully compatible Unlimited Unlimited back. File System = More with Windows. Consolidating = Creating a copy of features = security etc… Macs & Linux can read files but not write. the media. Codecs Codecs Wrappers/ Containers Video compression codecs: Audio compression codecs: Video wrappers: Lossy: Lossy:.MXF = Material eXchange Format H.264 = Internet. Inter-frame. AAC (Advanced Audio Coding)= Lossy &.OMF = Open Media Framework MPEG 2 = Moving Picture Experts Group. Very compressed. Equivalent to MP3 = Apple common SD/HD. Inter-frame. MP3 = Lossy compressed format = Music Lossy: MPEG 4 = Internet streaming = Ease of storage on mobiles..MP4 = Most common used for H264/265. AVC-I = Advanced Video Coding. I-frame only HD.MOV = Apple QuickTime files AVCHD = Long GOP domestic cameras Lossless:.JPEG = Joint Photographic Experts Group ProRes = Apple editing format. I–frame. M4A.FLV/ SWF = Flash video/ Small web format DNxHD = Avid HD editing format. I-frame. ALAC = Apple’s Lossless Audio Codec..AAF = Advanced Authoring Format DNxHR = Digital high resolution for UHD. I-frame. Lossless audio compression = Apple..MPG/ M2T FLAC =Free Lossless Audio Codec. Lossless Lossless: compressed music files. Lossless: DVCPRO HD = Panasonic HD format.WMV = Windows Media Video Uncompressed:.DPX = Digital Picture Exchange JPEG2000 (J2K) = 2:1 lossless compression (BOTH) AIFF = Alternative to WAV with better.MXF OP1A = Material eXchange Format VP9 = Android equivalent to H264 (BOTH) metadata support = Apple Operational Pattern AV1 (BOTH) PCM = Pulse-Code Modulation Wrappers for Delivery: Codecs for Delivery:.MXF AVC-I Lossy.MOV H265 = Half the size of H264 at the same quality Losing some data during compression..MP4 H264 Can result in a loss of quality (blurry image/ JPEG2000 loss of audio). DNxHD/ DNxHR Often used in circumstances where a small Wrappers/ Containers ProRes loss in quality is acceptable to save space. Audio wrappers: Looks for similar pixels in image and Lossless: similarity between frames. WAV = Waveform Audio File Format. MPEG = Codec AND Wrapper Uncompressed, great sound quality but large MP4 = Codec AND Wrapper file sizes. Lossless.BWAV = Broadcast WAV Preserving all data during compression. Reduce file size without losing any data. Looks for regular sequences or long runs of AVI = Audio Video Interleave. Windows. 1s or 0s. (BOTH) No significant savings for video/audio. Still Images Vector Lossy: AI, EPS, SVG JPEG (Joint Photographic Experts Group) = Has a maximum 8-bit depth and 3 channels. RASTER Based upon mathematical equations, rather than solid-coloured pixels Lossless: Re-sizing and processing = Easier TIFF (Tag Image File Format) = Supports all colours. Supports a higher bit depth. RASTER Will not go soft or have jagged lines due PNG (Portable Network Graphic) = Supports full colour RGB. Supports 24-bit RGB/ 32-bit RGBA. RASTER to rescaling. RAW (Unprocessed data) Can be scaled to any size without BMP (Bitmap) losing quality. ZIP (Zip Archive File) GIF (Graphics Interchange Format) = Least colour support. Limited to 256 colours but can support all Raster animation and transparency. JPG, PNG, TIFF PSD (Adobe Photoshop Document) AKA Bitmap images AI (Adobe Illustrator) VECTOR Composed of a grid of pixels EPS (Encapsulated PostScript) = Can be opened in illustration apps such as AI. VECTOR Each pixel contains colour information When you zoom in you may notice AVIF (AV1 Image File Format) (BOTH) = Supports 12-bit colour depth = HDR. individual pixels = affect image quality Lose quality when re-sized Long GOP Intra-frame compression (About Long = H264/ Short = ProRes quality) Every frame is treated as separate A GOP of 2 or more = Long GOP = Makes small files but are harder to create and play. image. Video compression method where frames are encoded in a sequence. The compression algorithm work to Only some frames are fully encoded (I Frames) while other frames store only the differences from reduce the file size by eliminating previous frames (B and P Frames). redundant data within that single frame. Allows for data reduction, making it efficient for storage, delivery and playback. Allows for higher quality. AVC-I, ProRes and DNx codecs. I Frame = (Intra-coded frame) Complete image of that frame B Frame = (Bi-directional frames) Reference past and future frames Inter-frame compression (About P Frame = (Predicted frames) Reference past frames playback) Looks at the differences between What is the first frame in Long GOP? = I (Don’t go more than 2 seconds without I-Frame) frames and only saves changes from What frame is there more of in Long GOP? = B one frame to the next. Efficient for storage as reduces file sizes Not reliable in the edit = Adding 1 frame can affect other frames or lead to quality degradation. and improves playback. MPEG, H264 and H265 Audio Network Types Loudness = EBU R.128 PAN = Personal Area Network Integrated measurement = Average over the whole programme Small Network = Transfer small files Short term – 3 second sliding window Devices connected via wireless network (Bluetooth) or wired Momentary – 400ms sliding window connections (USB) -23 LUFS = For compatibility with well-mixed older programmes using the old LAN = Local Area Network PPM spec. A group of devices that are located in the same building using private networks. Silences and low-level audio are not included in the average = Gated. WLAN = Wireless Local Network LAN but with a wireless connection. Audio Audio dBTP = Decibels True Peak CAN = Campus Area Network VU meter = Volume Unit = The A general unit for measuring sound A network that joins 2 or more LANs within a limited area. average volume level of an audio intensity. It can describe peak signal. levels without considering human MAN = Metropolitan Area Network perception of loudness. PPM = Peak Programme Meter = Programme will fail if it hirs -1dBTP SAN = Storage Area Network The peak level of an audio signal. = recommended level -3dBTP. High-speed network that stores and provides access to large LU = Loudness Unit amounts of data. Used for data storage. True Peak Meter = Measures all Measured over time and K-weighted Consists of multiple disk arrays, switches and servers. peak levels of an audio signal, (matches levels of different NOT affected by Network traffic = a Network all by itself. including inter-sample peaks = frequencies in the electrical signal Help prevent clipping and to the way our ears perceive them.) WAN = Wide Area Network distortion. LUFS = Loudness Unit Full Scale Largest type of network including multiple LANs, CANs and Measure perceived loudness in MANs. audio. Ensures consistency. Span over large geographical areas. -23 LUFS + 0.5LU = Target loudness Audio in USA averaged over entire programme. ATSC = Advanced Television SUBNET = Subnetwork (smaller networks) LRA = Loudness Range Systems Committee A85 A division of a bigger network Difference between the quiet and -24LKFS +2dB A router separates networks and subnets loud passages. Quietest = 10%. LKFS = Loudness K Can create however many subnets as needed to suit Loudest = 5%. weighted(similar to LUFS) business and separate network traffic. Recommended 18LU maximum. No Gate Measure the dialogue Router = Gateway/ doorway to every network. Default Gateway = A device that forwards data from one network to another. Allows devices to communicate from other networks. Black Levels 10-bit broadcast = 64 20-bit broadcast = 1024 White Levels 255? Timecode America 01:00;00 UK 10:00:00 How much of a HD programme can be in SD? = 25% How much of a HD programme can be archive footage? = 10%