ICEpdf
  1. ICEpdf
  2. PDF-289

Transparency grouping on colour space support

          Details

          • Type: Bug Bug
          • Status: Closed
          • Priority: Major Major
          • Resolution: Fixed
          • Affects Version/s: 6.0
          • Fix Version/s: 6.0.2
          • Component/s: Core/Parsing
          • Labels:
            None
          • Environment:
            any

            Description

            The pdf in question has an image that isn't properly clipped and obscures the underlying text. Normally this kind of issue falls under masking but in this case it's actually a transparency group issue.

            The Indexed colour space oft he image has transparency group definition which must be responsible for the transparency shown by acrobat.
            1. PDF File
              aging-asia.pdf
              244 kB
              Patrick Corless

              Issue Links

              blocks

              Bug - A problem which impairs or prevents the functions of the product. PDF-828 Grouped Transparenrcy is not rendered properly.

              • Major - Major loss of function.
              • Open

              Bug - A problem which impairs or prevents the functions of the product. PDF-299 PDF background color renders over top of text

              • Major - Major loss of function.
              • Closed

              Bug - A problem which impairs or prevents the functions of the product. PDF-373 Error clipping or specifying alpha in jpeg encoded images.

              • Major - Major loss of function.
              • Closed
              depends on

              Improvement - An improvement or enhancement to an existing feature or task. PDF-350 Enhance transparency groups implementation to avoid loss of render quality.

              • Major - Major loss of function.
              • Reopened
              duplicates

              Bug - A problem which impairs or prevents the functions of the product. PDF-275 DCTDecode transparency issue

              • Major - Major loss of function.
              • Closed
              is duplicated by

              Bug - A problem which impairs or prevents the functions of the product. PDF-417 Loss of color on generated images

              • Major - Major loss of function.
              • Closed

                Activity

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                Patrick Corless added a comment -

                sample file

                Show
                Patrick Corless added a comment - sample file
                Hide
                Permalink
                Patrick Corless added a comment -

                Moving to 4.3.

                Show
                Patrick Corless added a comment - Moving to 4.3.
                Hide
                Permalink
                Patrick Corless added a comment -

                Another example of transparency group issue.

                Show
                Patrick Corless added a comment - Another example of transparency group issue.
                Hide
                Permalink
                Patrick Corless added a comment -

                Moving target to 5.1 in the hope that we can tackle transparency groups for this release.

                Show
                Patrick Corless added a comment - Moving target to 5.1 in the hope that we can tackle transparency groups for this release.
                Hide
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                Patrick Corless added a comment -

                Did a little more work on this issue/topic. I tried to apply a simple mask on the image in question using white as the transparency pixel. The PDF renders correctly but unfortunately there are other side effects in other documents. From what I can tell from the spec we should be treating each xForm in the group as a separate layer and in this case the back text would be used as a mask on the image. This may still be possible to implement but as of current, we need to save each layer as a buffered image and do the masking which is both memory intensive and results in a much lower quality render.

                Show
                Patrick Corless added a comment - Did a little more work on this issue/topic. I tried to apply a simple mask on the image in question using white as the transparency pixel. The PDF renders correctly but unfortunately there are other side effects in other documents. From what I can tell from the spec we should be treating each xForm in the group as a separate layer and in this case the back text would be used as a mask on the image. This may still be possible to implement but as of current, we need to save each layer as a buffered image and do the masking which is both memory intensive and results in a much lower quality render.
                Hide
                Permalink
                Patrick Corless added a comment -

                A lot of work has gone into improving our support for transparency groups particularly around various blending modes. As result this PDF is now correctly rendering using a multiply blend mode.

                Show
                Patrick Corless added a comment - A lot of work has gone into improving our support for transparency groups particularly around various blending modes. As result this PDF is now correctly rendering using a multiply blend mode.
                Hide
                Permalink
                Patrick Corless added a comment -

                Marking as fixed.

                Show
                Patrick Corless added a comment - Marking as fixed.

                  People

                  • Assignee:
                    Patrick Corless
                    Reporter:
                    Patrick Corless
                  • Votes:
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                    Dates

                    • Created:
                      Updated:
                      Resolved: