Microsoft Example Container Format ALL ALL HD Picture Aspect Ratio 4
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Sony Microsoft Example Toshiba Panasonic Container Format ALL ALL HD Sample Pixel Aspect Ratio[1] 1:1, 10:11, 40:33, 1:1, 10:11, 40:33, 4:3, plus 12:11, 4:3 16:11 for 50Hz Picture Aspect Ratio 4:3, 16:9 1.33, 1.78, 1.85, 2.35 Encoded frame 4:3 , 16:9 Resolution 720x480 , PD 320x240, 1280x720, 416x240, SD 1920x1080, plus 640x480, 720x576 for 50Hz 720x480NTSC, 864x480, HD 1280x720, 1440x1080, 1920x1080 Overscan / cropping Optional for AVC cropping devices to crop parameters L+R to 704 with specified in overscan flag in stream and ISO AVC elementary Track size stream equals decoder output size e.g. 1080 or 704, not 1088 or 720 encoded size Black padding Send coordinates OK, but encode of active picture AVC cropping parameters of actual picture area Horizontal sub-sampling No [40:33 IS Yes, e.g. “subsampling”] 720x480 16:9 NTSC 1440x1080 16:9 Quantization range[2] 16-235, 0-253 16-235, 0-253 legal range as visible range, not defined in Rec clipped, as 601 and 709 defined in Rec 601 and 709 Color space [3] Req 601 for PD, Req 601 for PD, SD, Req 709 for SD; Req 709 for HD HD, negative RGB OK 50 hertz or not? Optional for Decode required, Europe etc publication regional Frame rates 29.97, 23.976 14.99, 23.976, plus 25 for 50Hz 25, 29.97, 50, Progressive / interlace Both Both59.94 Recommended practice topics Interlaced temporal sub-sampling, filtering Optimized for progressive display, default AVC 4:2:0 subsample locations Gamma curve, render intent, display Encoded with adaptation studio monitor gamma. Display correction applied by device (e.g. 2.4 for computer or hand held, 1.5 for home theater) [1] e.g. NTSC, PAL, anamorphic, sq, … [2] e.g. 16-235, 0-255, +/-128, … [3] e.g. Rec 601, 709; negative coefficients Notes to Discuss: • [MS] Attempting to pre-correct for limited devices at encoding (e.g. vertical resolution filtering to prevent “CRT flicker”, encoding letterbox bars, encoded pulldown, etc.) usually compromises high end devices (progressive displays, 120Hz, motion interpolation, automatic PAR adaptation, etc.) • [MS] Might recommend safe areas based on device cropping to 4:3 • [MS] Clarification of “exact scan” pixel dimensions to avoid unnecessary scaling (e.g. 704 or 720 = 4:3? = 16:9 anamorphic?) Display intent must be specified explicitly using correct SAR in h.264 • [SPE] Proposes a new MP4 box for optional frame crop. • Crop box parameters shall be constant through an entire track • Crop box must exist in every sync sample for random access. • Luma crop parameters must be a multiple of 2 to compensate for 4:2:0 subsampling of chroma pixels. • Top and Bottom luma crop parameters are limited to a multiple of 4 to compensate for field based presentations in 4:2:0. • Composition objects such as subtitles require positioning methods to coordinate with frame cropping. This is not included in the scope of this box and must be defined elsewhere. • [MS] Vertical coding size can be any number of lines up to defined maximum number. • [MS] Some of current internet streaming distributed contents are encoded with respect to aspect ratio of the source video. • PC software platforms are capable of handling as it is done today • CE platforms may not be capable of handling flexible sized videoformat • Limited guaranteed video format supported in LSI • Increase in testing –can not guarantee every combination • [SPE] Define active video window in MP4 file format as DECE unique user data • [SPE] Contents are encoded with embedded black lines as done today (for non-internet streaming contents) • [SPE] PC software uses MP4 file format to crop the embedded black lines as post process before displaying the contents. • [SPE] CE platform displays/outputs with black lines –may optionally crop the black lines. [MS] Attempting to pre-correct for limited devices at encoding (e.g. vertical resolution filtering to prevent “CRT flicker”, encoding letterbox bars, encoded pulldown, etc.) usually compromises high end devices (progressive displays, 120Hz, motion interpolation, automatic PAR adaptation, etc.) [MS] Clarification of “exact scan” pixel dimensions to avoid unnecessary scaling (e.g. 704 or 720 = 4:3? = 16:9 anamorphic?) Display intent must be specified explicitly using correct SAR in h.264 Luma crop parameters must be a multiple of 2 to compensate for 4:2:0 subsampling of chroma pixels. Top and Bottom luma crop parameters are limited to a multiple of 4 to compensate for field based presentations in 4:2:0. Composition objects such as subtitles require positioning methods to coordinate with frame cropping. This is not included in the scope of this box and must be defined elsewhere. [MS] Vertical coding size can be any number of lines up to defined maximum number. [MS] Some of current internet streaming distributed contents are encoded with respect to aspect ratio of the source video. [SPE] Contents are encoded with embedded black lines as done today (for non-internet streaming contents) [SPE] PC software uses MP4 file format to crop the embedded black lines as post process before displaying the contents. [SPE] CE platform displays/outputs with black lines –may optionally crop the black lines. [MS] Attempting to pre-correct for limited devices at encoding (e.g. vertical resolution filtering to prevent “CRT flicker”, encoding letterbox bars, encoded pulldown, etc.) usually compromises high end devices (progressive displays, 120Hz, motion interpolation, automatic PAR adaptation, etc.) [MS] Clarification of “exact scan” pixel dimensions to avoid unnecessary scaling (e.g. 704 or 720 = 4:3? = 16:9 anamorphic?) Display intent must be specified explicitly using correct SAR in h.264 Composition objects such as subtitles require positioning methods to coordinate with frame cropping. This is not included in the scope of this box and must be defined elsewhere. [MS] Attempting to pre-correct for limited devices at encoding (e.g. vertical resolution filtering to prevent “CRT flicker”, encoding letterbox bars, encoded pulldown, etc.) usually compromises high end devices (progressive displays, 120Hz, motion interpolation, automatic PAR adaptation, etc.) Sample Pixel Aspect Ratio Pixel aspect ratio (often abbreviated PAR) is a mathematical ratio that describes how the width of pixels in a digital image compares to their height. Most digital imaging systems describe an image as a grid of very small but nonetheless square pixels. However, some imaging systems, especially those which must maintain compatibility with Standard-definition television motion pictures, define an image as a grid of rectangular pixels in which the width of the pixel is slightly different from that of its height. Pixel Aspect Ratio describes this difference. Use of Pixel Aspect Ratio mostly involves pictures pertaining to standard-definition television and some other exceptional cases. Most other imaging systems, including those which comply with SMPTE standards and practices, use square pixels. Pixel aspect ratios of common video formats Pixel Aspect Ratio values for common standard-definition video formats are listed below. Note that for each video format, three different types of Pixel Aspect Ratio values are listed: Rec.601, a Rec.601-compliant value, which is considered the real Pixel Aspect Ratio of standard-definition video of that type. (Read Explanation) Digital, which is roughly equivalent to Rec.601 and is more suitable to use in Digital Video Editing software. (Read Explanation) Picture Pixel Aspect Ratio Video Dimension Pixel Aspect Ratio (Decimal) System s Rec.601 Digital Rec.601 Digital Standard (4:3) PAL 720×576 (e.g. 576i) 704×576 59:54:00 12:11 Widescreen (16:9)352×288 PAL 118:81 16:11 Standard (4:3) NTSC 720×480 (e.g. 480i) 704×480 10:11 Widescreen (16:9)352×240 NTSC 40:33:00 Picture Aspect Ratio TV - 1.33 (4:3), 1.78 (16:9); 25i, 30i, 50p, 60p (1.33/1.85 open matte) Movies – 1.33 (4:3), 1.85, 2.35, 2.40; 24p (25p, 30p minor use) Common aspect ratios: 1.33 (4:3 TV), 1.78 (16:9 TV), 1.85 2.0, 2.33, 2.4(film), 16:9 anamorphic 708x483 SMPTE D1 display aperture 704x480 ATSC 4:3? 720x480 DVD 4:3? The aspect ratio of an image is its width divided by its height. Aspect ratios are mathematically expressed as x :y (pronounced "x-to-y") and x×y (pronounced "x-by-y"). The most common aspect ratios used today in the presentation of films in movie theaters are 1.85:1 and 2.39:1[1]. Two common videographic aspect ratios are 4:3 (1.33:1), universal for standard-definition video formats, and 16:9 (1.78:1), universal to high-definition television and European digital television. Other cinema and video aspect ratios exist, but are used infrequently. In still camera photography, the most common aspect ratios are 4:3, 3:2, and more recently being found in consumer cameras, previously only commonly seen in professional cameras, 16:9[2][3]. Other aspect ratios, such as 5:4, 6:7, and 1:1 (square format), are used in photography as well. Converting formats of unequal ratios is done by either cropping the original image to the receiving format's aspect ratio (zooming), by adding horizontal mattes (letterboxing) or vertical mattes (pillarboxing) to retain the original format's aspect ratio, or by distorting the image to fill the receiving format's ratio. Cinematographic aspect ratios are usually denoted as a decimal fraction width to unit height, while videographic aspect ratios are usually denoted by ratios of whole numbers. Resolution The display resolution of a digital television or display typically refers to the number of distinct pixels in each dimension that can be displayed.