Save to PDF: embeds JPEGs using /FlateDecode instead of /DCTDecode
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
Inkscape |
New
|
Wishlist
|
Unassigned | ||
inkscape (Ubuntu) |
New
|
Undecided
|
Unassigned |
Bug Description
Binary package hint: inkscape
A JPEG image is already compressed using /DCTDecode and can be embedded straight into an output PDF without altering or recompressing the content.
In the example given, I used Inkscape for composition, placing an affine-transformed semi-transparent PNG image of a narwhale over a large JPEG background showing Big Ben and the London Eye. The input files were 1.2 MB and and 33 kB and the total output size of the PDF should ideally have been the same. Instead, the PDF output file was 8 MB and the inspecting it shows that /FlateDecode was being inefficiently used for the JPEG stream.
Ideally JPEG streams should be output using /DCTDecode to retain the original compression efficiency and avoid any recompression.
Related earlier reports:
Bug #168708 in Inkscape: “embedded jpg exported to eps&pdf as non-jpg”
Bug #171104 in Inkscape: “compressed JPEG/TIF in exported EPS”
Bug #171774 in Inkscape: “possibility to choose compression level for PDF output”
Bug #449453 in Inkscape: “Inkscape needs more options for saving PDF”
Bug #672135 in Inkscape: “[Feature] Additional PDF conversion options”
Duplicate of bug #168708?