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Common Digital Audio Formats…

The following table lists key characteristics of common digital image file formats.

Format Bit-depth (per sample) Sampling rate (kHz) Channels Lossy compression Lossless compression Embedded metadata
PCM Wave (WAV)*
MPEG Layer-3 (MP3) 48 2
x
x
Vorbis (OGG) 200 255
x
PCM Audio Interchange File Format (AIFF)*
x
Free Lossless Audio Codec (FLAC) 32 1,048.57 8
x
x
Advanced Audio Coding (AAC) 192 48
x
Microsoft Windows Media Audio (WMA) 24 96 8
x
x
x
Dolby Digital AC-3 (AC3) 16 48 6
x
Dolby TrueHD 24 96 14
x
Digital Theater System Coherent Acoustics (DTS) 24 48 6
x
DTS-HD Master Audio (Stereo mode) 24 192 2
x
DTS-HD Master Audio (Multichannel mode) 24 96 8
x

*Wave and AIFF are container formats that are used in conjunction with various audio codecs, which may impose limits on each property.

Posted: October 15th, 2008
Categories: Articles
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Common Digital Image Formats…

The following table lists key characteristics of common digital image file formats.

Format Bit depth (per pixel) Color model Lossy compression Lossless compression Layers Alpha channels Embedded timecode Additional features
Adobe Digital Negative (DNG) Various Various
x
x
x
x
Supports all feature of TIFF specification, various metadata
xAdobe Photoshop Document (PSD) Various Various
x
x
x
Supports vectors, parametric image operations, color profiles, other metadata
Kodak Cineon (CIN) 30 Logarithmic RGB, linear RGB
x
Can store key numbers, other metadata
CompuServe Graphical Interchange Format (GIF) 8 Indexed RGB Supports animation, keyed alpha
SMPTE Digital Picture Exchange (DPX) 24, 30 Logarithmic RGB, linear RGB
x
Supports all features of Cineon specification
JPEG 24 Linear RGB
x
x
JPEG-2000 Various Various
x
x
x
Supports color profiles, other metadata
TIFF Various Various
x
x
x
x
Several variants of the TIFF format are available, such as LogLuv and Pixar, allowing for different dynamic ranges, supports color profiles, other metadata
OpenEXR 48 Logarithmic HDR
x
x
Covers 9.6 orders of magnitude with 0.1% precision, can store key numbers, other metadata
Radiance 32 Logarithmic HDR
x
Covers 76 orders of magnitude with 1.0% precision
Portable Network Graphics (PNG) 24 Linear RGB
x
x
Targa (TGA) 24 Linear RGB
x
Windows Bitmap (BMP) 8, 24 Linear RGB
Posted: October 15th, 2008
Categories: Articles
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Standard Video Characteristics…

The following table lists key characteristics of popular analogue and digital video formats. Figures shown are the maximum supported by the format specification in each case.

Format Frame rate Field order Color sampling Bandwidth Compression Precision
Digital Betacam (NTSC) 29.97 Upper first 4:2:2 90 Mb/s 2.31:1 10-bit
Digital Betacam (PAL) 25 Upper first 4:2:2 90 Mb/s 2.31:1 10-bit
D1 (NTSC) 29.97 Lower first 4:2:2 270 Mb/s 1:1 8-bit
D1 (PAL) 25 Lower first 4:2:2 270 Mb/s 1:1 8-bit
Digital8 (NTSC) 29.97 Lower first 4:1:1 25 Mb/s 5:1 8-bit
Digital8 (PAL) 25 Lower first 4:2:0 25 Mb/s 5:1 8-bit
DV-SP (NTSC) 29.97 Lower first 4:1:1 25 Mb/s 5:1 8-bit
DV-SP (PAL) 25 Lower first 4:2:0 25 Mb/s 5:1 8-bit
DVCAM (NTSC) 29.97 Lower first 4:1:1 25 Mb/s 5:1 8-bit
DVCAM (PAL) 25 Lower first 4:2:0 25 Mb/s 5:1 8-bit
DVCPRO (NTSC) 29.97 Lower first 4:1:1 25 Mb/s 5:1 8-bit
DVCPRO (PAL) 25 Lower first 4:1:1 25 Mb/s 5:1 8-bit
DVCPRO 50 29.97 Lower first 4:2:2 50 Mb/s 3.3:1 8-bit
DVCPRO-P 30p n/a 4:2:0 50 Mb/s 5:1 8-bit
DVD (NTSC) 29.97 Upper first 4:2:0 9.8 Mb/s 22:1 (MPEG-2) 8-bit
DVD (PAL) 25 Upper first 4:2:0 9.8 Mb/s 22:1 (MPEG-2) 8-bit
Betacam SX (NTSC) 29.97 Upper first 4:2:2 18 Mb/s 10:1 (MPEG-2) 8-bit
Betacam SX (PAL) 25 Upper first 4:2:2 18 Mb/s 10:1 (MPEG-2) 8-bit
HDV @720p 25p, 30p n/a 4:2:0 25 Mb/s 22.5:1 (MPEG-2) 8-bit
HDV @1080i 25, 30 Upper first 4:2:0 25 Mb/s 22.5:1 (MPEG-2) 8-bit
DVCProHD-100 25, 29.97, 29.97p, 30, 30p Lower first 4:2:2 100 Mb/s 6.7:1 8-bit
HDD5 23.98p, 24p, 25, 25p, 29.97, 29.97p, 30, 30p Upper first 4:2:2 250 Mb/s 4:1 (8-bit), 5:1 (10-bit) 8-bit, 10-bit
HDCAM 23.98p, 24p, 25, 25p, 29.97, 29.97p, 30, 30p Upper first 3:1:1 143 Mb/s 7.1:1 8-bit
HDCAM SR 23.98p, 24p, 25, 25p, 29.97, 29.97p, 30, 30p Upper first 4:4:4, 4:4:4 (log), 4:2:2 880 Mb/s (4:4:4), 440 Mb/s (4:2:2) 4.2:1 (MPEG-4, 4:4:4), 2.7:1 (MPEG-4, 4:2:2) 10-bit
Blu-ray 23.98p, 24p, 25, 25p, 29.97, 29.97p, 30, 30p Upper first 4:2:0 40 Mb/s 25:1 8-bit
Posted: October 15th, 2008
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Film Dimensions…

The following table lists the physical dimensions for various film formats.

Format Width (mm) Height (mm) Aspect ratio
16mm 10.26 7.49 1.37
Super-16 12.52 7.42 1.69
35mm (Academy) 21.94 16.00 1.37
35mm (Cinemascope) 21.94 18.59 2.35 (unsqueezed)
35mm (Full aperture) 24.89 18.67 1.33
Vista-vision (8-perf) 37.71 25.17 1.5
Posted: October 15th, 2008
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Final Cut Pro Batch List Specification…

As far as I can tell, there is no “formal” (nor informal, for that matter) specification for a Final Cut Pro Batch List anywhere, despite being in regular use (this is unfortunately the case for several file types in regular use in post-production). FCP’s manual provides a few hints, but nothing completely definitive.

So here goes:

  1. The first line of the batch file must contain the headings of the relevant fields, separated by tabs. These must be named precisely (see below for possible field headings).
  2. The fields “Name”, “Media Start”, “Media End” and “Reel” are required.
  3. The information for clips must be provided on one line per clip.
  4. Folders in a project are defined on a line by starting with an asterisk (*), a space, and the folder name (e.g. “* AAA_cut_aways”). All clips listed after that label will be placed are in that folder. Strangely though, FCP seems to ignore these labels when importing a batch list.
  5. The file must be plain text.

As of Final Cut Pro 6.0.3, any of the following field headings can be used:

  • Name
  • Duration
  • In
  • Out
  • Media Start
  • Media End
  • Tracks – must be in the form “1V,2A” (for 1 video track and 2 audio tracks in this case)
  • Good – “Yes”/”No”
  • Log Note
  • Label
  • Label 2
  • Audio
  • Frame Size – must be in the form “pixel_width x pixel_height” (e.g. “1920 x 1080″)
  • Vid Rate – must be in the form “25 fps”
  • Compressor
  • Data Rate – must be in the form “2048/sec”
  • Aud Rate – must be in the form “96.0 KHz”
  • Aud Format
  • Alpha
  • Reverse Alpha – “Yes”/”No”
  • Composite
  • Pixel Aspect
  • Anamorphic – “Yes”/”No”
  • Field Dominance – “Upper (Odd)” or “Lower (Even)”
  • Description
  • Scene
  • Shot/Take
  • Angle
  • Reel
  • Master Comment 1
  • Master Comment 2
  • Comment 1
  • Comment 2
  • Master Clip – “Yes”/”No”
  • Offline – “Yes”/”No”
  • Last Modified – Must be in the form “Tue, Mar 4, 2008, 17:19″
  • Film Safe – “Yes”/”No”

Other things to note:

  • Although many people are under the impression that right-clicking on a sequence and choosing Export->Batch List will produce a list that only contains clips used in the selected sequence, this is actually not the case. Exported batch lists will always contain all clips in the project. UPDATE (25/August/09): See the comment by Josh below…
  • Exporting a batch list from FCP will only export field data for columns that are visible in the project. So if you have the “Master Comment 1″ column hidden, that data won’t get exported.
  • The frame rate gets determined by the project that the list is imported into, and is not specified in the list directly.

UPDATE (07/April/09): It was brought to my attention that there is an issue with manually creating text files for Batch Lists. It seems that yet another requirement of the Batch List is that every line must be terminated by ASCII character 13 (rather than ASCII character 10). Not doing so will produce the error that one or more headings are invalid.

I have created an AppleScript that will convert files that are producing this error.

Batch List Text Conversion AppleScript

Posted: May 9th, 2008
Categories: Articles
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