Changeset 846 for trunk/src/3rdparty/libjpeg/jdmaster.c

Timestamp:

May 5, 2011, 5:36:53 AM (14 years ago)

Author:

Dmitry A. Kuminov

Message:

trunk: Merged in qt 4.7.2 sources from branches/vendor/nokia/qt.

Location:

trunk

Files:

• . (modified) (1 prop)
• src/3rdparty/libjpeg/jdmaster.c (modified) (6 diffs)

trunk/src/3rdparty/libjpeg/jdmaster.c

@@ -3 +3 @@
  *
  * Copyright (C) 1991-1997, Thomas G. Lane.
+ * Modified 2002-2009 by Guido Vollbeding.
  * This file is part of the Independent JPEG Group's software.
  * For conditions of distribution and use, see the accompanying README file.
@@ -62 +63 @@
     return FALSE;
   /* furthermore, it doesn't work if we've scaled the IDCTs differently */
-  if (cinfo->comp_info[0].DCT_scaled_size != cinfo->min_DCT_scaled_size ||
-      cinfo->comp_info[1].DCT_scaled_size != cinfo->min_DCT_scaled_size ||
-      cinfo->comp_info[2].DCT_scaled_size != cinfo->min_DCT_scaled_size)
+  if (cinfo->comp_info[0].DCT_h_scaled_size != cinfo->min_DCT_h_scaled_size ||
+      cinfo->comp_info[1].DCT_h_scaled_size != cinfo->min_DCT_h_scaled_size ||
+      cinfo->comp_info[2].DCT_h_scaled_size != cinfo->min_DCT_h_scaled_size ||
+      cinfo->comp_info[0].DCT_v_scaled_size != cinfo->min_DCT_v_scaled_size ||
+      cinfo->comp_info[1].DCT_v_scaled_size != cinfo->min_DCT_v_scaled_size ||
+      cinfo->comp_info[2].DCT_v_scaled_size != cinfo->min_DCT_v_scaled_size)
     return FALSE;
   /* ??? also need to test for upsample-time rescaling, when & if supported */
@@ -83 +87 @@
 GLOBAL(void)
 jpeg_calc_output_dimensions (j_decompress_ptr cinfo)
-/* Do computations that are needed before master selection phase */
+/* Do computations that are needed before master selection phase.
+ * This function is used for full decompression.
+ */
 {
 #ifdef IDCT_SCALING_SUPPORTED
@@ -94 +100 @@
     ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
 
+  /* Compute core output image dimensions and DCT scaling choices. */
+  jpeg_core_output_dimensions(cinfo);
+
 #ifdef IDCT_SCALING_SUPPORTED
 
-  /* Compute actual output image dimensions and DCT scaling choices. */
-  if (cinfo->scale_num * 8 <= cinfo->scale_denom) {
-    /* Provide 1/8 scaling */
-    cinfo->output_width = (JDIMENSION)
-      jdiv_round_up((long) cinfo->image_width, 8L);
-    cinfo->output_height = (JDIMENSION)
-      jdiv_round_up((long) cinfo->image_height, 8L);
-    cinfo->min_DCT_scaled_size = 1;
-  } else if (cinfo->scale_num * 4 <= cinfo->scale_denom) {
-    /* Provide 1/4 scaling */
-    cinfo->output_width = (JDIMENSION)
-      jdiv_round_up((long) cinfo->image_width, 4L);
-    cinfo->output_height = (JDIMENSION)
-      jdiv_round_up((long) cinfo->image_height, 4L);
-    cinfo->min_DCT_scaled_size = 2;
-  } else if (cinfo->scale_num * 2 <= cinfo->scale_denom) {
-    /* Provide 1/2 scaling */
-    cinfo->output_width = (JDIMENSION)
-      jdiv_round_up((long) cinfo->image_width, 2L);
-    cinfo->output_height = (JDIMENSION)
-      jdiv_round_up((long) cinfo->image_height, 2L);
-    cinfo->min_DCT_scaled_size = 4;
-  } else {
-    /* Provide 1/1 scaling */
-    cinfo->output_width = cinfo->image_width;
-    cinfo->output_height = cinfo->image_height;
-    cinfo->min_DCT_scaled_size = DCTSIZE;
-  }
   /* In selecting the actual DCT scaling for each component, we try to
    * scale up the chroma components via IDCT scaling rather than upsampling.
    * This saves time if the upsampler gets to use 1:1 scaling.
-   * Note this code assumes that the supported DCT scalings are powers of 2.
+   * Note this code adapts subsampling ratios which are powers of 2.
    */
   for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
        ci++, compptr++) {
-    int ssize = cinfo->min_DCT_scaled_size;
-    while (ssize < DCTSIZE &&
-           (compptr->h_samp_factor * ssize * 2 <=
-            cinfo->max_h_samp_factor * cinfo->min_DCT_scaled_size) &&
-           (compptr->v_samp_factor * ssize * 2 <=
-            cinfo->max_v_samp_factor * cinfo->min_DCT_scaled_size)) {
+    int ssize = 1;
+    while (cinfo->min_DCT_h_scaled_size * ssize <=
+           (cinfo->do_fancy_upsampling ? DCTSIZE : DCTSIZE / 2) &&
+           (cinfo->max_h_samp_factor % (compptr->h_samp_factor * ssize * 2)) == 0) {
       ssize = ssize * 2;
     }
-    compptr->DCT_scaled_size = ssize;
+    compptr->DCT_h_scaled_size = cinfo->min_DCT_h_scaled_size * ssize;
+    ssize = 1;
+    while (cinfo->min_DCT_v_scaled_size * ssize <=
+           (cinfo->do_fancy_upsampling ? DCTSIZE : DCTSIZE / 2) &&
+           (cinfo->max_v_samp_factor % (compptr->v_samp_factor * ssize * 2)) == 0) {
+      ssize = ssize * 2;
+    }
+    compptr->DCT_v_scaled_size = cinfo->min_DCT_v_scaled_size * ssize;
+
+    /* We don't support IDCT ratios larger than 2. */
+    if (compptr->DCT_h_scaled_size > compptr->DCT_v_scaled_size * 2)
+        compptr->DCT_h_scaled_size = compptr->DCT_v_scaled_size * 2;
+    else if (compptr->DCT_v_scaled_size > compptr->DCT_h_scaled_size * 2)
+        compptr->DCT_v_scaled_size = compptr->DCT_h_scaled_size * 2;
   }
 
@@ -150 +142 @@
     compptr->downsampled_width = (JDIMENSION)
       jdiv_round_up((long) cinfo->image_width *
-                    (long) (compptr->h_samp_factor * compptr->DCT_scaled_size),
-                    (long) (cinfo->max_h_samp_factor * DCTSIZE));
+                    (long) (compptr->h_samp_factor * compptr->DCT_h_scaled_size),
+                    (long) (cinfo->max_h_samp_factor * cinfo->block_size));
     compptr->downsampled_height = (JDIMENSION)
       jdiv_round_up((long) cinfo->image_height *
-                    (long) (compptr->v_samp_factor * compptr->DCT_scaled_size),
-                    (long) (cinfo->max_v_samp_factor * DCTSIZE));
-  }
-
-#else /* !IDCT_SCALING_SUPPORTED */
-
-  /* Hardwire it to "no scaling" */
-  cinfo->output_width = cinfo->image_width;
-  cinfo->output_height = cinfo->image_height;
-  /* jdinput.c has already initialized DCT_scaled_size to DCTSIZE,
-   * and has computed unscaled downsampled_width and downsampled_height.
-   */
+                    (long) (compptr->v_samp_factor * compptr->DCT_v_scaled_size),
+                    (long) (cinfo->max_v_samp_factor * cinfo->block_size));
+  }
 
 #endif /* IDCT_SCALING_SUPPORTED */
@@ -373 +356 @@
   jinit_inverse_dct(cinfo);
   /* Entropy decoding: either Huffman or arithmetic coding. */
-  if (cinfo->arith_code) {
-    ERREXIT(cinfo, JERR_ARITH_NOTIMPL);
-  } else {
-    if (cinfo->progressive_mode) {
-#ifdef D_PROGRESSIVE_SUPPORTED
-      jinit_phuff_decoder(cinfo);
-#else
-      ERREXIT(cinfo, JERR_NOT_COMPILED);
-#endif
-    } else
-      jinit_huff_decoder(cinfo);
+  if (cinfo->arith_code)
+    jinit_arith_decoder(cinfo);
+  else {
+    jinit_huff_decoder(cinfo);
   }