Compression and downsampling options for pdfs – Adobe InDesign CS4 User Manual
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USING INDESIGN CS4
Interactive Elements
Exports all movies, sounds, and buttons. Acrobat 4.0 and 5.0 require that sounds be embedded
and movies be linked. Acrobat 6.0 and later support linking and embedding of movies and sounds.
Multimedia
Lets you specify how to embed or link movies and sounds:
•
Use Object Settings
Embeds movies and sounds according to the settings in the Sound Options and Movie Options
dialog box.
•
Link All
Links sound and movie clips placed in the document. If you choose not to embed media clips in the PDF
file, be sure to place the media clips in the same folder as the PDF.
•
Embed All
Embeds all movies and sounds, regardless of embed settings on individual objects.
Note: The Multimedia option is only available when Compatibility is set to Acrobat 6 (PDF 1.5) or later and Interactive
Elements is selected. When Compatibility is set to Acrobat 4 (PDF 1.3) or Acrobat 5 (PDF 1.4) and Interactive Elements
is selected, InDesign embeds movies and sounds according to the individual object settings.
See also
Compression and downsampling options for PDFs
When exporting documents to Adobe PDF, you can compress text and line art, and compress and downsample bitmap
images. Depending on the settings you choose, compression and downsampling can significantly reduce the size of a
PDF file with little or no loss of detail and precision.
The Compression area of the Export Adobe PDF dialog box is divided into three sections. Each section provides the
following options for compressing and resampling color, grayscale, or monochrome images in your artwork.
Downsampling
If you plan to use the PDF file on the web, use downsampling to allow for higher compression. If you
plan to print the PDF file at high resolution, check with your prepress service provider before setting compression and
downsampling options.
You should also consider whether users need to magnify a page. For example, if you are creating a PDF document of
a map, consider using a higher image resolution so that users can zoom in on the map.
Downsampling refers to decreasing the number of pixels in an image. To downsample color, grayscale, or
monochrome images, choose an interpolation method—average downsampling, bicubic downsampling, or
subsampling—and enter the desired resolution (in pixels per inch). Then enter a resolution in the For Images Above
text box. All images with resolution above this threshold will be downsampled.
The interpolation method you choose determines how pixels are deleted:
•
Average Downsampling To
Averages the pixels in a sample area and replaces the entire area with the average pixel
color at the specified resolution.
•
Subsampling To
Chooses a pixel in the center of the sample area and replaces the entire area with that pixel color.
Subsampling significantly reduces the conversion time compared with downsampling but results in images that are
less smooth and continuous.
Updated 18 June 2009