webp minor cleanups and sync to git

BUG=none
TEST=none

Review URL: http://codereview.chromium.org/4248001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@64683 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 35 insertions, 39 deletions

diff --git a/third_party/libwebp/frame.c b/third_party/libwebp/frame.c
index 1e1aadc..b7bb16a 100644
--- a/third_party/libwebp/frame.c
+++ b/third_party/libwebp/frame.c
@@ -9,7 +9,6 @@
 //
 // Author: Skal (pascal.massimino@gmail.com)
 
-#include <stddef.h>
 #include <stdlib.h>
 #include "vp8i.h"
 
@@ -224,52 +223,49 @@ void VP8StoreBlock(VP8Decoder* const dec) {
 }
 
 void VP8FilterRow(VP8Decoder* const dec, VP8Io* io) {
+  const int extra_y_rows = kFilterExtraRows[dec->filter_type_];
+  const int ysize = extra_y_rows * dec->cache_y_stride_;
+  const int uvsize = (extra_y_rows / 2) * dec->cache_uv_stride_;
+  const int first_row = (dec->mb_y_ == 0);
+  const int last_row = (dec->mb_y_ >= dec->mb_h_ - 1);
+  uint8_t* const ydst = dec->cache_y_ - ysize;
+  uint8_t* const udst = dec->cache_u_ - uvsize;
+  uint8_t* const vdst = dec->cache_v_ - uvsize;
   int mb_x;
   for (mb_x = 0; mb_x < dec->mb_w_; ++mb_x) {
     DoFilter(dec, mb_x, dec->mb_y_);
   }
-  {
-    const int extra_y_rows = kFilterExtraRows[dec->filter_type_];
-    const int ysize = extra_y_rows * dec->cache_y_stride_;
-    const int uvsize = (extra_y_rows / 2) * dec->cache_uv_stride_;
-    uint8_t* const ydst = dec->cache_y_ - ysize;
-    uint8_t* const udst = dec->cache_u_ - uvsize;
-    uint8_t* const vdst = dec->cache_v_ - uvsize;
-    if (io->put) {
-      int y_end;
-      if (dec->mb_y_ > 0) {
-        io->mb_y = dec->mb_y_ * 16 - extra_y_rows;
-        io->y = ydst;
-        io->u = udst;
-        io->v = vdst;
-        if (dec->mb_y_ < dec->mb_h_ - 1) {
-          y_end = io->mb_y + 16;
-        } else {
-          y_end = io->height;   // last macroblock row.
-        }
-      } else {   // first macroblock row.
-        io->mb_y = 0;
-        y_end = 16 - extra_y_rows;
-        io->y = dec->cache_y_;
-        io->u = dec->cache_u_;
-        io->v = dec->cache_v_;
-      }
-      if (y_end > io->height) {
-        y_end = io->height;
-      }
-      io->mb_h = y_end - io->mb_y;
-      io->put(io);
+  if (io->put) {
+    int y_start = dec->mb_y_ * 16;
+    int y_end = y_start + 16;
+    if (!first_row) {
+      y_start -= extra_y_rows;
+      io->y = ydst;
+      io->u = udst;
+      io->v = vdst;
+    } else {
+      io->y = dec->cache_y_;
+      io->u = dec->cache_u_;
+      io->v = dec->cache_v_;
     }
-    // rotate top samples
-    if (dec->mb_y_ < dec->mb_h_ - 1) {
-      memcpy(ydst, ydst + 16 * dec->cache_y_stride_, ysize);
-      memcpy(udst, udst + 8 * dec->cache_uv_stride_, uvsize);
-      memcpy(vdst, vdst + 8 * dec->cache_uv_stride_, uvsize);
+    if (!last_row) {
+      y_end -= extra_y_rows;
+    }
+    if (y_end > io->height) {
+      y_end = io->height;
     }
+    io->mb_y = y_start;
+    io->mb_h = y_end - y_start;
+    io->put(io);
+  }
+    // rotate top samples
+  if (!last_row) {
+    memcpy(ydst, ydst + 16 * dec->cache_y_stride_, ysize);
+    memcpy(udst, udst + 8 * dec->cache_uv_stride_, uvsize);
+    memcpy(vdst, vdst + 8 * dec->cache_uv_stride_, uvsize);
   }
 }
 
-
 //-----------------------------------------------------------------------------
 // Main reconstruction function.
 
diff --git a/third_party/libwebp/vp8.c b/third_party/libwebp/vp8.c
index 76fc74e..234f361 100644
--- a/third_party/libwebp/vp8.c
+++ b/third_party/libwebp/vp8.c
@@ -223,7 +223,7 @@ int VP8GetHeaders(VP8Decoder* const dec, VP8Io* const io) {
   // Paragraph 9.1
   {
     const uint32_t bits = buf[0] | (buf[1] << 8) | (buf[2] << 16);
-    frm_hdr = &dec->frm_hdr_;    
+    frm_hdr = &dec->frm_hdr_;
     frm_hdr->key_frame_ = !(bits & 1);
     frm_hdr->profile_ = (bits >> 1) & 7;
     frm_hdr->show_ = (bits >> 4) & 1;