From 06c3ee0204caa54421007bc29f3ae203436058ce Mon Sep 17 00:00:00 2001
From: John Whitington <john@coherentgraphics.co.uk>
Date: Thu, 10 Oct 2024 17:38:34 +0200
Subject: [PATCH] Fix image_resolution / image-resolution-json

---
 Changes        |  4 ++++
 cpdfcommand.ml |  3 +--
 cpdfimage.ml   | 15 +++++++++------
 3 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/Changes b/Changes
index 03ef689..95b1050 100644
--- a/Changes
+++ b/Changes
@@ -23,6 +23,10 @@ Extended features:
 
 o Rectangle may be specified as x y x' y' rather than x y w h
 
+Fixes:
+
+o -image-resolution-json was listing all images
+
 * = Supported by a grant from NLnet
 
 2.7.1 (July 2024)
diff --git a/cpdfcommand.ml b/cpdfcommand.ml
index dd190c7..c7512a2 100644
--- a/cpdfcommand.ml
+++ b/cpdfcommand.ml
@@ -4405,8 +4405,7 @@ let go () =
           let images = Cpdfimage.image_resolution pdf range f in
             iter
               (function (pagenum, xobject, w, h, wdpi, hdpi, objnum) ->
-                  if wdpi < f || hdpi < f then
-                    Printf.printf "%i, %s, %i, %i, %f, %f, %i\n" pagenum xobject w h wdpi hdpi objnum)
+                 Printf.printf "%i, %s, %i, %i, %f, %f, %i\n" pagenum xobject w h wdpi hdpi objnum)
                images
   | Some ListImages ->
       let pdf = get_single_pdf args.op true in
diff --git a/cpdfimage.ml b/cpdfimage.ml
index 72b6d53..4804e07 100644
--- a/cpdfimage.ml
+++ b/cpdfimage.ml
@@ -193,7 +193,7 @@ type xobj =
 
 let image_results = ref []
 
-let rec image_resolution_page pdf page pagenum dpi images =
+let rec image_resolution_page pdf page pagenum images =
   try
     let pageops = Pdfops.parse_operators pdf page.Pdfpage.resources page.Pdfpage.content
     and transform = ref [ref Pdftransform.i_matrix] in
@@ -239,7 +239,7 @@ let rec image_resolution_page pdf page pagenum dpi images =
                              Pdfpage.rest = Pdf.Dictionary []}
                           in
                             let newpdf = Pdfpage.change_pages false pdf [page] in
-                              image_resolution newpdf [pagenum] dpi
+                              image_resolution newpdf [pagenum]
                    | (pagenum, name, Image (w, h), objnum) ->
                        let lx = Pdfunits.inches (distance_between o x) Pdfunits.PdfPoint in
                        let ly = Pdfunits.inches (distance_between o y) Pdfunits.PdfPoint in
@@ -268,7 +268,7 @@ let rec image_resolution_page pdf page pagenum dpi images =
     with
       e -> Printf.printf "Error %s\n" (Printexc.to_string e); flprint "\n"
 
-and image_resolution pdf range dpi =
+and image_resolution pdf range =
   let images = ref [] in
     Cpdfpage.iter_pages
       (fun pagenum page ->
@@ -322,13 +322,16 @@ and image_resolution pdf range dpi =
         iter
           (function (pagenum, images) ->
              let page = select pagenum pages in
-               image_resolution_page pdf page pagenum dpi images)
+               image_resolution_page pdf page pagenum images)
           pagesplits
 
+let is_below_dpi dpi (_, _, _, _, wdpi, hdpi, _) =
+  wdpi < dpi || hdpi < dpi
+
 let image_resolution pdf range dpi =
   image_results := [];
-  image_resolution pdf range dpi;
-  rev !image_results
+  image_resolution pdf range;
+  rev (keep (is_below_dpi dpi) !image_results)
 
 let image_resolution_json pdf range dpi =
   let images = image_resolution pdf range dpi in