Bug 45224

Summary: pdftoppm-exported JPEGs should retain ppi info
Product: poppler Reporter: Jorge Hernández Valiñani <chocolate.camera>
Component: utilsAssignee: poppler-bugs <poppler-bugs>
Status: RESOLVED FIXED QA Contact:
Severity: normal    
Priority: medium    
Version: unspecified   
Hardware: x86 (IA32)   
OS: Mac OS X (All)   
Whiteboard:
i915 platform: i915 features:
Attachments: patch to fix

Description Jorge Hernández Valiñani 2012-01-25 03:42:40 UTC 
When converting a PDF to JPEG using a custom resolution like in the command below:

	pdftoppm -jpeg -r 214 in.pdf out

the output JPEG does not seem to contain any ppi info (and hence defaults to 72 in most graphic apps). It should retain the custom ppi used in the command to generate it, just like tiff files do with the command:

	pdftoppm -tiff -r 214 in.pdf out

Using Macports' pdftoppm version 0.18.2 from the port poppler @0.18.2 (graphics/poppler)
Comment 1 Adrian Johnson 2012-01-25 04:29:45 UTC 
Created attachment 56136 [details] [review]
patch to fix

Problem is caused by calling jpeg_set_defaults(&cinfo) after setting the resolution which overwrites the resolution.
Comment 2 Albert Astals Cid 2012-01-26 09:46:40 UTC 
Adrian, should the
 cinfo.in_color_space = colorMode; /* colorspace of input image */
also be after 
 jpeg_set_defaults(&cinfo);
?
Comment 3 Adrian Johnson 2012-01-26 12:55:17 UTC 
(In reply to comment #2)
> Adrian, should the
>  cinfo.in_color_space = colorMode; /* colorspace of input image */
> also be after 
>  jpeg_set_defaults(&cinfo);
> ?

No. The libjpeg documentation for jpeg_set_defaults() states:

  "This routine sets all JPEG parameters to reasonable defaults, using
   only the input image's color space (field in_color_space, which must
   already be set in cinfo)"
Comment 4 Albert Astals Cid 2012-01-26 13:44:51 UTC 
Makes sense then, please commit :-)
Comment 5 Adrian Johnson 2012-01-26 14:26:42 UTC 
Committed.

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