PSD: Fix thumbnail extraction for PSD files (AcademySoftwareFoundation#3668)

Fixes AcademySoftwareFoundation#3660

In investigating this issue, I also noticed that now that IOProxy
support can be relied on, the old code that in the psd reader that
directly fumbles with libjpeg is not needed and can be replaced by
just a couple of lines to make an ImageBuf read from an IOProxy.

And it fixes the bug, too. So I'm not even going to try to figure
out what was going wrong with the old code.

Author: lgritz

src/jpeg.imageio/jpeg_pvt.h

@@ -86,7 +86,6 @@ class JpgInput final : public ImageInput {
     void jpegerror(my_error_ptr myerr, bool fatal = false);
 
 private:
-    FILE* m_fd;
     std::string m_filename;
     int m_next_scanline;   // Which scanline is the next to read?
     bool m_raw;            // Read raw coefficients, not scanlines
@@ -101,7 +100,6 @@ class JpgInput final : public ImageInput {
 
     void init()
     {
-        m_fd            = NULL;
         m_raw           = false;
         m_cmyk          = false;
         m_fatalerr      = false;

src/psd.imageio/CMakeLists.txt

@@ -2,7 +2,5 @@
 # SPDX-License-Identifier: BSD-3-Clause
 # https://github.com/OpenImageIO/oiio
 
-add_oiio_plugin (psdinput.cpp jpeg_memory_src.cpp
-                 INCLUDE_DIRS ${JPEG_INCLUDE_DIR}
-                 LINK_LIBRARIES JPEG::JPEG)
+add_oiio_plugin (psdinput.cpp)
 

src/psd.imageio/jpeg_memory_src.cpp

@@ -20,7 +20,7 @@
 #include <OpenImageIO/imagebufalgo.h>
 #include <OpenImageIO/tiffutils.h>
 
-#include "jpeg_memory_src.h"
+// #include "jpeg_memory_src.h"
 #include "psd_pvt.h"
 
 OIIO_PLUGIN_NAMESPACE_BEGIN
@@ -265,13 +265,6 @@ class PSDInput final : public ImageInput {
 
     //Load thumbnail resource, used for resources 1033 and 1036
     bool load_resource_thumbnail(uint32_t length, bool isBGR);
-    //For thumbnail loading
-    struct thumbnail_error_mgr {
-        jpeg_error_mgr pub;
-        jmp_buf setjmp_buffer;
-    };
-    METHODDEF(void)
-    thumbnail_error_exit(j_common_ptr cinfo);
 
     //Layers
     bool load_layers();
@@ -1270,9 +1263,6 @@ PSDInput::load_resource_thumbnail(uint32_t length, bool isBGR)
     uint32_t compressed_size;
     uint16_t bpp;
     uint16_t planes;
-    int stride;
-    jpeg_decompress_struct cinfo;
-    thumbnail_error_mgr jerr;
     uint32_t jpeg_length = length - 28;
 
     bool ok = read_bige<uint32_t>(format) && read_bige<uint32_t>(width)
@@ -1312,40 +1302,13 @@ PSDInput::load_resource_thumbnail(uint32_t length, bool isBGR)
         return false;
     }
 
-    cinfo.err           = jpeg_std_error(&jerr.pub);
-    jerr.pub.error_exit = thumbnail_error_exit;
-    if (setjmp(jerr.setjmp_buffer)) {
-        jpeg_destroy_decompress(&cinfo);
-        errorfmt("[Image Resource] [JPEG Thumbnail] libjpeg error");
-        return false;
-    }
     std::string jpeg_data(jpeg_length, '\0');
     if (!ioread(&jpeg_data[0], jpeg_length))
         return false;
 
-    jpeg_create_decompress(&cinfo);
-    jpeg_memory_src(&cinfo, (unsigned char*)&jpeg_data[0], jpeg_length);
-    jpeg_read_header(&cinfo, TRUE);
-    jpeg_start_decompress(&cinfo);
-    stride = cinfo.output_width * cinfo.output_components;
-    ImageSpec thumbspec(cinfo.output_width, cinfo.output_height, 3, TypeUInt8);
-    m_thumbnail.reset(thumbspec);
-    // jpeg_destroy_decompress will deallocate this
-    JSAMPLE** buffer = (*cinfo.mem->alloc_sarray)((j_common_ptr)&cinfo,
-                                                  JPOOL_IMAGE, stride, 1);
-    while (cinfo.output_scanline < cinfo.output_height) {
-        if (jpeg_read_scanlines(&cinfo, buffer, 1) != 1) {
-            jpeg_finish_decompress(&cinfo);
-            jpeg_destroy_decompress(&cinfo);
-            errorfmt("[Image Resource] [JPEG Thumbnail] libjpeg error");
-            return false;
-        }
-        m_thumbnail.get_pixels(ROI(0, width, cinfo.output_scanline,
-                                   cinfo.output_scanline + 1, 0, 1, 0, 3),
-                               TypeUInt8, buffer[0]);
-    }
-    jpeg_finish_decompress(&cinfo);
-    jpeg_destroy_decompress(&cinfo);
+    Filesystem::IOMemReader thumbblob(jpeg_data.data(), jpeg_length);
+    m_thumbnail = ImageBuf("thumbnail.jpg", 0, 0, nullptr, nullptr, &thumbblob);
+    m_thumbnail.read(0, 0, true);
 
     // Set these attributes for the merged composite only (subimage 0)
     composite_attribute("thumbnail_width", (int)width);
@@ -1358,15 +1321,6 @@ PSDInput::load_resource_thumbnail(uint32_t length, bool isBGR)
 
 
 
-void
-PSDInput::thumbnail_error_exit(j_common_ptr cinfo)
-{
-    thumbnail_error_mgr* mgr = (thumbnail_error_mgr*)cinfo->err;
-    longjmp(mgr->setjmp_buffer, 1);
-}
-
-
-
 bool
 PSDInput::load_layers()
 {