Fixing nits

- Const Handling of picture object, removed bitwriter from encoder.

Change-Id: Id943854de09324de81cca615ada960390c4b8152

src/enc/picture.c

@@ -105,13 +105,15 @@ int WebPPictureAlloc(WebPPicture* const picture) {
         mem += uv0_size;
       }
     } else {
+      const uint64_t argb_size = (uint64_t)width * height;
+      const uint64_t total_size = argb_size * sizeof(*picture->argb);
       if (width <= 0 || height <= 0 ||
-          width >= 0x4000 || height >= 0x4000) {
+          argb_size >= (1ULL << 40) ||
+          (size_t)total_size != total_size) {
         return 0;
       }
       WebPPictureFree(picture);   // erase previous buffer
-      picture->argb = (uint32_t*)malloc(width * height *
-                                        sizeof(*picture->argb));
+      picture->argb = (uint32_t*)malloc(total_size);
       if (picture->argb == NULL) return 0;
       picture->argb_stride = width;
     }
@@ -526,8 +528,11 @@ static int Import(WebPPicture* const picture,
       for (y = 0; y < height; ++y) {
         for (x = 0; x < width; ++x) {
           const int offset = step * x + y * rgb_stride;
-          const uint32_t argb = 0xff000000 | (r_ptr[offset] << 16) |
-              (g_ptr[offset] << 8) | (b_ptr[offset]);
+          const uint32_t argb =
+              0xff000000 |
+              (r_ptr[offset] << 16) |
+              (g_ptr[offset] <<  8) |
+              (b_ptr[offset]);
           picture->argb[x + y * picture->argb_stride] = argb;
         }
       }
@@ -537,8 +542,11 @@ static int Import(WebPPicture* const picture,
       for (y = 0; y < height; ++y) {
         for (x = 0; x < width; ++x) {
           const int offset = step * x + y * rgb_stride;
-          const uint32_t argb = (a_ptr[offset] << 24) | (r_ptr[offset] << 16) |
-              (g_ptr[offset] << 8) | (b_ptr[offset]);
+          const uint32_t argb =
+              (a_ptr[offset] << 24) |
+              (r_ptr[offset] << 16) |
+              (g_ptr[offset] <<  8) |
+              (b_ptr[offset]);
           picture->argb[x + y * picture->argb_stride] = argb;
         }
       }

src/enc/vp8l.c

@@ -5,7 +5,7 @@
 //  Additional IP Rights Grant:  http://www.webmproject.org/license/additional/
 // -----------------------------------------------------------------------------
 //
-// main entry for the decoder
+// main entry for the lossless encoder.
 //
 // Author: Vikas Arora (vikaas.arora@gmail.com)
 //
@@ -52,7 +52,7 @@ static int ApplyCrossColorFilter(VP8LEncoder* const enc) {
   return 1;
 }
 
-static void EvalEmergingPalette(VP8LEncoder* const enc) {
+static void EvalColorCache(VP8LEncoder* const enc) {
   (void)enc;
 }
 
@@ -81,13 +81,14 @@ static WebPEncodingError WriteRiffHeader(VP8LEncoder* const enc,
   return VP8_ENC_OK;
 }
 
-static WebPEncodingError WriteImage(VP8LEncoder* const enc) {
+static WebPEncodingError WriteImage(VP8LEncoder* const enc,
+                                    VP8LBitWriter* const bw) {
   size_t riff_size, vp8l_size, webpll_size, pad;
-  WebPPicture* const pic = enc->pic_;
+  const WebPPicture* const pic = enc->pic_;
   WebPEncodingError err = VP8_ENC_OK;
-  const uint8_t* const webpll_data = VP8LBitWriterFinish(&enc->bw_);
+  const uint8_t* const webpll_data = VP8LBitWriterFinish(bw);
 
-  webpll_size = VP8LBitWriterNumBytes(&enc->bw_);
+  webpll_size = VP8LBitWriterNumBytes(bw);
   vp8l_size = SIGNATURE_SIZE + webpll_size;
   pad = vp8l_size & 1;
   vp8l_size += pad;
@@ -111,14 +112,12 @@ static WebPEncodingError WriteImage(VP8LEncoder* const enc) {
   return VP8_ENC_OK;
 
  Error:
-  WebPEncodingSetError(pic, err);
   return err;
 }
 
 static VP8LEncoder* InitVP8LEncoder(const WebPConfig* const config,
                                     WebPPicture* const picture) {
   VP8LEncoder* enc;
-  const int kEstmatedEncodeSize = (picture->width * picture->height) >> 1;
   (void)config;
 
   enc = (VP8LEncoder*)malloc(sizeof(*enc));
@@ -133,23 +132,18 @@ static VP8LEncoder* InitVP8LEncoder(const WebPConfig* const config,
   // TODO: Use config.quality to initialize histo_bits_ and transform_bits_.
   enc->histo_bits_ = 4;
   enc->transform_bits_ = 4;
-  VP8LBitWriterInit(&enc->bw_, kEstmatedEncodeSize);
 
   return enc;
 }
 
-static WebPEncodingError WriteImageSize(VP8LEncoder* const enc) {
-  WebPEncodingError status = VP8_ENC_OK;
+static void WriteImageSize(VP8LEncoder* const enc, VP8LBitWriter* const bw) {
   WebPPicture* const pic = enc->pic_;
   const int width = pic->width - 1;
-  const int height = pic->height - 1;
-  if (width < 0x4000 && height < 0x4000) {
-    VP8LWriteBits(&enc->bw_, kImageSizeBits, width);
-    VP8LWriteBits(&enc->bw_, kImageSizeBits, height);
-  } else {
-    status = VP8_ENC_ERROR_BAD_DIMENSION;
-  }
-  return status;
+  const int height = pic->height -1;
+  assert(width < WEBP_MAX_DIMENSION && height < WEBP_MAX_DIMENSION);
+
+  VP8LWriteBits(bw, kImageSizeBits, width);
+  VP8LWriteBits(bw, kImageSizeBits, height);
 }
 
 static void DeleteVP8LEncoder(VP8LEncoder* enc) {
@@ -161,11 +155,22 @@ int VP8LEncodeImage(const WebPConfig* const config,
   int ok = 0;
   VP8LEncoder* enc = NULL;
   WebPEncodingError err = VP8_ENC_OK;
+  VP8LBitWriter bw;
 
   if (config == NULL || picture == NULL) return 0;
-  if (picture->argb == NULL) return 0;
+
+  if (picture->argb == NULL) {
+    err = VP8_ENC_ERROR_NULL_PARAMETER;
+    goto Error;
+  }
+
   enc = InitVP8LEncoder(config, picture);
-  if (enc == NULL) goto Error;
+  if (enc == NULL) {
+    err = VP8_ENC_ERROR_NULL_PARAMETER;
+    goto Error;
+  }
+
+  VP8LBitWriterInit(&bw, (picture->width * picture->height) >> 1);
 
   // ---------------------------------------------------------------------------
   // Analyze image (entropy, num_palettes etc)
@@ -177,11 +182,7 @@ int VP8LEncodeImage(const WebPConfig* const config,
   }
 
   // Write image size.
-  err = WriteImageSize(enc);
-  if (err != VP8_ENC_OK) {
-    ok = 0;
-    goto Error;
-  }
+  WriteImageSize(enc, &bw);
 
   // ---------------------------------------------------------------------------
   // Apply transforms and write transform data.
@@ -196,8 +197,8 @@ int VP8LEncodeImage(const WebPConfig* const config,
     if (!ApplyCrossColorFilter(enc)) goto Error;
   }
 
-  if (enc->use_emerging_palette_) {
-    EvalEmergingPalette(enc);
+  if (enc->use_color_cache) {
+    EvalColorCache(enc);
   }
 
   // ---------------------------------------------------------------------------
@@ -206,14 +207,14 @@ int VP8LEncodeImage(const WebPConfig* const config,
   ok = EncodeImageInternal(enc);
   if (!ok) goto Error;
 
-  err = WriteImage(enc);
+  err = WriteImage(enc, &bw);
   if (err != VP8_ENC_OK) {
     ok = 0;
     goto Error;
   }
 
  Error:
-  VP8LBitWriterDestroy(&enc->bw_);
+  VP8LBitWriterDestroy(&bw);
   DeleteVP8LEncoder(enc);
   if (!ok) {
     // TODO(vikasa): err is not set for all error paths. Set default err.

src/enc/vp8li.h

@@ -44,9 +44,7 @@ typedef struct {
   int num_palette_colors;
   int use_predict_;
   int use_cross_color_;
-  int use_emerging_palette_;
-
-  VP8LBitWriter bw_;
+  int use_color_cache;
 } VP8LEncoder;
 
 //------------------------------------------------------------------------------

src/enc/webpenc.c

@@ -367,7 +367,7 @@ int WebPEncode(const WebPConfig* const config, WebPPicture* const pic) {
     if (pic->argb == NULL)
       return WebPEncodingSetError(pic, VP8_ENC_ERROR_NULL_PARAMETER);
 
-    ok = VP8LEncodeImage(config, pic);
+    ok = VP8LEncodeImage(config, pic);  // Sets pic->error in case of problem.
   }
 
   return ok;

src/utils/bit_writer.h

@@ -90,7 +90,7 @@ static WEBP_INLINE uint8_t* VP8LBitWriterFinish(VP8LBitWriter* const bw) {
   return bw->buf_;
 }
 
-// Returns 1 on success.
+// Returns 0 in case of memory allocation error.
 int VP8LBitWriterInit(VP8LBitWriter* const bw, size_t expected_size);
 
 void VP8LBitWriterDestroy(VP8LBitWriter* const bw);
@@ -111,7 +111,7 @@ void VP8LBitWriterDestroy(VP8LBitWriter* const bw);
 // For n bits, we take the last 5 bytes, OR that with high bits in BYTE-0,
 // and locate the rest in BYTE+1 and BYTE+2.
 //
-// returns 1 on success.
+// VP8LBitWriter's error_ flag is set in case of  memory allocation error.
 void VP8LWriteBits(VP8LBitWriter* const bw, int n_bits, uint32_t bits);
 
 //------------------------------------------------------------------------------

src/webp/encode.h

@@ -218,7 +218,7 @@ struct WebPPicture {
 
   WebPProgressHook progress_hook;  // if not NULL, called while encoding.
 
-  int use_argb_input;     // Flag for encoder to read argb pixels as input.
+  int use_argb_input;     // Flag for encoder to use argb pixels as input.
   uint32_t* argb;         // Pointer to argb (32 bit) plane.
   int argb_stride;        // This is stride in pixels units, not bytes.
 };