Aspect Ratio, Crop and Resample
From IRIDAS Online Documentation
Contents |
Overview
Aspect Ratio, Crop and Resample can be applied interactively in FrameCycler Professional, DDS, DI and SpeedGrade HD,XR,DI 2007/2008 using the panels underneath the timeline. If sequences or .ircp files are loaded via the command line you can predefine all three criteria at once (please refer to the command line documentation for further information).
Aspect Ratio Menu and AspectRatio.fcps
If you are using a special pixel aspect ratio, for example for anamorphic frames, you can choose between two presets in the pixel aspect ratio menu or add additional presets to the menu.
Changing the pixel aspect ratio is done in the display in real-time. Unlike resampling, this command does not require reloading the frames into RAM.
To add custom aspect ratios to the menu open AspectRatio.fcps with a Text Editor such as Wordpad or TextEdit. AspectRatio.fcps is located in the Settings directory of your IRIDAS application. It will show the two presets delivered with the application:
Anamorphic (stretch 2:1) 2:1 Anamorphic (squash 1:0.5) 1:0.5
To add a custom preset simply copy an existing entry and replace the part before the TAB with the display name for the menu you'd like to use, then replace the actual aspect ratio after the TAB with the aspect ratio you'd like to add. If you'd like to add 1.33:1 this would look like this example:
AVID 1.33 (1.33:1) 1.33:1
After adding a custom preset save and close the file. The new preset will be available next time you launch your IRIDAS application.
Crop Menu and Crop.fcps
The Crop Menu allows you to resize your frames by cropping away part of the image. This can be useful for removing black borders to decrease frame size or to check how the sequence will appear on different display devices (for example how a Cinemascope sequence looks on a HD TV set).
After cropping, the image width or height will always be equal to, or less than, the actual frame size. FrameCycler and SpeedGrade will not accept larger values. For example if you try to crop a 100 pixel wide sequence to 200 pixels width, it will remain 100 pixel wide.
To customize the Crop Menu open Crop.fcps with a Text Editor such as Wordpad or TextEdit. Crop.fcps is located in the Settings directory of your IRIDAS application.
You can simplify the menu by taking out entries that are not relevant to your workflow or porject. A crop preset always includes the actual crop value and any number of Display Names. If one Display Name is sufficient you can make the Display for 2.35:1 much shorter. The Original preset is:
2.35 : 1 CinemaScope 2.35 : 1 UltraPanavision 2.35 : 1 Panavision 2.35 : 1 Technirama 2.35 : 1 Todd-AO 2.35 : 1 Super 35 2.35 : 1
The shortest version for this preset would be:
2.35 : 1 CinemaScope 2.35 : 1
You can also use crop values based on pixel values, Crop.fcps already includes the following:
PAL Video W720 H576 NTSC Video W720 H486 720p W1280 H720 1080p W1920 H1080
To add an additional pixel value based crop format simply add one line to this list, put a Display Name first, hit TAB, then put a value for W and for H.
A third method of defining crop values in Crop.fcps is using values in percentage or absolute pixels. This method allows to define values for left, top, right and bottom individually:
10% Border 10% 10% R10% B10% 20% Border 20% 20% R20% B20% 100 Pixel Border 100 100 R100 B100
If you'd like to crop 200 pixels from top and bottom, 140 from left and right, add this line to Crop.fcps:
200/140 Pixel Border 140 200 R140 B200
After adding a custom preset or changing the list of presets save and close the file. The updated list of presets will be available next time you launch your IRIDAS application.
Resample Menu and Resample.fcps
The Resample Menu allows you to change the resolution of a sequence. In contrast to the Aspect Ratio or Zoom function, the Resample function actually changes the number of pixels in the image. If you apply a preset in the resample panel, the image cache is cleared and the frames are reloaded into RAM. You can use this feature to load more HD or 2K frames at once into FrameCycler Professional to extend its RAM playback capacity.
To add custom resample values to the menu open Resample.fcps with a Text Editor such as Wordpad or TextEdit. AspectRatio.fcps is located in the Settings directory of your IRIDAS application. A custom preset can be added in either percentages or pixel data. To add a preset for resampling to 93.75% (2K -> HD) to the menu add the following line to Resample.fcps:
HD to 2K 93.75% 93.75%
The same result can be achieved by using pixel data - this will produce a result that is independent of the resolution of the source format:
1080p 1920 1080
After adding a custom preset save and close the file. The new preset will be available next time you launch your IRIDAS application.