Frame-interleaved output

This page applies to Harlequin v13.1r0 and later; and to Harlequin MultiRIP but not Harlequin Core

In frame‐interleaved output, the RIP passes the plugin all the bits for one color component on a page before any bits of the next color component. As with the other color types, the color components can appear in any order. Frame‐interleaving is therefore like sending independent color separations. In frame‐interleaving, however, all separations appear on the same raster, and therefore the same pagebuffer, thereby appearing to the user as a complete page. There is no need for specialized separation impositions. The RIP's Roam feature understands this format: when you roam a frame‐interleaved pagebuffer you see a colored page, including any spot colors present in the job.

Frame‐interleaved output is intended mainly for driving color printing devices that require their color data in separated but contiguous form. An example of such a device is a dye‐sublimation printer, which has a ribbon that is made up of three or four alternated sheets of process color, applied during repeated passes over the paper.

• The handling of frame‐interleaved output allows an arbitrary number of channel frames (including two). d_linescopied and similar fields now reach values of numChannels times the imageHeight rather than three or four times imageHeight as stated in earlier editions of this manual. Unused lines in the last band of each frame should not be added to d_linescopied .

The following shows how to setup a CMYK color frame interleave. To change the CompositeOrder to YMCK you would change it as shown below:

    <<
      /InterleavingStyle 4
      /ProcessColorModel /DeviceCMYK
      /SeparationDetails
    <<
      /SeparationStyle 4
      /CompositeColorNames [ /Cyan /Magenta /Yellow /Black ]
      /CompositeOrder [ /Yellow /Magenta /Cyan /Black ]
    >>
      /ValuesPerComponent 256
      /Halftone false
    >> setpagedevice

When the page has been processed, the colorants and the number of bits for frame interleaving are described in the pageHeader structure's colorValues and colorBits fields respectively. This is exactly as for the other raster types. (The pageHeader structure describes the pageHeader structure.)

As with all rasters, frame‐interleaved rasters are supplied in bands. However, note the following about frame‐interleaved rasters:

• The last band of each colorant generally contains fewer lines than all of the others.
• Each colorant starts in a new band, not contiguously in the same band at the end of the previous colorant.
• imageHeight in pageHeader is still the number of scan lines in the picture, not the number of partial lines in all the colorants.
• d_linescopied , d_linesripped , and d_linesprinted are interpreted as recording the number of image lines respectively copied, ripped, and printed. Therefore, they do not reset to zero at the end of each colorant, but continue counting until numChannels times imageHeight is reached.