Add commment for jpeg parameters.

Bug: None
Test: Try bots
Change-Id: I7b90731e828169af96b3e0b8f8821635cff57755
Reviewed-on: https://chromium-review.googlesource.com/c/1308819Reviewed-by: Frank Barchard <fbarchard@chromium.org>

README.chromium

 Name: libyuv
 URL: http://code.google.com/p/libyuv/
-Version: 1722
+Version: 1724
 License: BSD
 License File: LICENSE
 

include/libyuv/convert.h

@@ -375,11 +375,13 @@ int ARGB4444ToI420(const uint8_t* src_argb4444,
                    int height);
 
 #ifdef HAVE_JPEG
+// src_mjpg is pointer to raw jpeg bytes in memory
+// src_size_mjpg is size of jpeg in bytes
 // src_width/height provided by capture.
 // dst_width/height for clipping determine final size.
 LIBYUV_API
-int MJPGToI420(const uint8_t* sample,
-               size_t sample_size,
+int MJPGToI420(const uint8_t* src_mjpg,
+               size_t src_size_mjpg,
                uint8_t* dst_y,
                int dst_stride_y,
                uint8_t* dst_u,
@@ -393,8 +395,8 @@ int MJPGToI420(const uint8_t* sample,
 
 // JPEG to NV21
 LIBYUV_API
-int MJPGToNV21(const uint8_t* sample,
-               size_t sample_size,
+int MJPGToNV21(const uint8_t* src_mjpg,
+               size_t src_size_mjpg,
                uint8_t* dst_y,
                int dst_stride_y,
                uint8_t* dst_vu,
@@ -406,8 +408,8 @@ int MJPGToNV21(const uint8_t* sample,
 
 // Query size of MJPG in pixels.
 LIBYUV_API
-int MJPGSize(const uint8_t* sample,
-             size_t sample_size,
+int MJPGSize(const uint8_t* src_mjpg,
+             size_t src_size_mjpg,
              int* width,
              int* height);
 #endif

include/libyuv/convert_argb.h

@@ -627,8 +627,8 @@ int AR30ToAB30(const uint8_t* src_ar30,
 // src_width/height provided by capture
 // dst_width/height for clipping determine final size.
 LIBYUV_API
-int MJPGToARGB(const uint8_t* sample,
-               size_t sample_size,
+int MJPGToARGB(const uint8_t* src_mjpg,
+               size_t src_size_mjpg,
                uint8_t* dst_argb,
                int dst_stride_argb,
                int src_width,

include/libyuv/mjpeg_decoder.h

@@ -26,7 +26,7 @@ namespace libyuv {
 extern "C" {
 #endif
 
-LIBYUV_BOOL ValidateJpeg(const uint8_t* sample, size_t sample_size);
+LIBYUV_BOOL ValidateJpeg(const uint8_t* src_mjpg, size_t src_size_mjpg_size);
 
 #ifdef __cplusplus
 }  // extern "C"

include/libyuv/version.h

@@ -11,6 +11,6 @@
 #ifndef INCLUDE_LIBYUV_VERSION_H_
 #define INCLUDE_LIBYUV_VERSION_H_
 
-#define LIBYUV_VERSION 1723
+#define LIBYUV_VERSION 1724
 
 #endif  // INCLUDE_LIBYUV_VERSION_H_

source/convert_jpeg.cc

@@ -89,12 +89,12 @@ static void JpegI400ToI420(void* opaque,
 
 // Query size of MJPG in pixels.
 LIBYUV_API
-int MJPGSize(const uint8_t* sample,
-             size_t sample_size,
+int MJPGSize(const uint8_t* src_mjpg,
+             size_t src_size_mjpg,
              int* width,
              int* height) {
   MJpegDecoder mjpeg_decoder;
-  LIBYUV_BOOL ret = mjpeg_decoder.LoadFrame(sample, sample_size);
+  LIBYUV_BOOL ret = mjpeg_decoder.LoadFrame(src_mjpg, src_size_mjpg);
   if (ret) {
     *width = mjpeg_decoder.GetWidth();
     *height = mjpeg_decoder.GetHeight();
@@ -107,8 +107,8 @@ int MJPGSize(const uint8_t* sample,
 // TODO(fbarchard): review src_width and src_height requirement. dst_width and
 // dst_height may be enough.
 LIBYUV_API
-int MJPGToI420(const uint8_t* sample,
-               size_t sample_size,
+int MJPGToI420(const uint8_t* src_mjpg,
+               size_t src_size_mjpg,
                uint8_t* dst_y,
                int dst_stride_y,
                uint8_t* dst_u,
@@ -119,14 +119,14 @@ int MJPGToI420(const uint8_t* sample,
                int src_height,
                int dst_width,
                int dst_height) {
-  if (sample_size == kUnknownDataSize) {
+  if (src_size_mjpg == kUnknownDataSize) {
     // ERROR: MJPEG frame size unknown
     return -1;
   }
 
   // TODO(fbarchard): Port MJpeg to C.
   MJpegDecoder mjpeg_decoder;
-  LIBYUV_BOOL ret = mjpeg_decoder.LoadFrame(sample, sample_size);
+  LIBYUV_BOOL ret = mjpeg_decoder.LoadFrame(src_mjpg, src_size_mjpg);
   if (ret && (mjpeg_decoder.GetWidth() != src_width ||
               mjpeg_decoder.GetHeight() != src_height)) {
     // ERROR: MJPEG frame has unexpected dimensions
@@ -180,9 +180,9 @@ int MJPGToI420(const uint8_t* sample,
       ret = mjpeg_decoder.DecodeToCallback(&JpegI400ToI420, &bufs, dst_width,
                                            dst_height);
     } else {
-      // TODO(fbarchard): Implement conversion for any other colorspace/sample
-      // factors that occur in practice.
-      // ERROR: Unable to convert MJPEG frame because format is not supported
+      // TODO(fbarchard): Implement conversion for any other
+      // colorspace/subsample factors that occur in practice. ERROR: Unable to
+      // convert MJPEG frame because format is not supported
       mjpeg_decoder.UnloadFrame();
       return 1;
     }
@@ -249,8 +249,8 @@ static void JpegI400ToNV21(void* opaque,
 
 // MJPG (Motion JPeg) to NV21
 LIBYUV_API
-int MJPGToNV21(const uint8_t* sample,
-               size_t sample_size,
+int MJPGToNV21(const uint8_t* src_mjpg,
+               size_t src_size_mjpg,
                uint8_t* dst_y,
                int dst_stride_y,
                uint8_t* dst_vu,
@@ -259,14 +259,14 @@ int MJPGToNV21(const uint8_t* sample,
                int src_height,
                int dst_width,
                int dst_height) {
-  if (sample_size == kUnknownDataSize) {
+  if (src_size_mjpg == kUnknownDataSize) {
     // ERROR: MJPEG frame size unknown
     return -1;
   }
 
   // TODO(fbarchard): Port MJpeg to C.
   MJpegDecoder mjpeg_decoder;
-  LIBYUV_BOOL ret = mjpeg_decoder.LoadFrame(sample, sample_size);
+  LIBYUV_BOOL ret = mjpeg_decoder.LoadFrame(src_mjpg, src_size_mjpg);
   if (ret && (mjpeg_decoder.GetWidth() != src_width ||
               mjpeg_decoder.GetHeight() != src_height)) {
     // ERROR: MJPEG frame has unexpected dimensions
@@ -382,22 +382,22 @@ static void JpegI400ToARGB(void* opaque,
 // TODO(fbarchard): review src_width and src_height requirement. dst_width and
 // dst_height may be enough.
 LIBYUV_API
-int MJPGToARGB(const uint8_t* sample,
-               size_t sample_size,
+int MJPGToARGB(const uint8_t* src_mjpg,
+               size_t src_size_mjpg,
                uint8_t* dst_argb,
                int dst_stride_argb,
                int src_width,
                int src_height,
                int dst_width,
                int dst_height) {
-  if (sample_size == kUnknownDataSize) {
+  if (src_size_mjpg == kUnknownDataSize) {
     // ERROR: MJPEG frame size unknown
     return -1;
   }
 
   // TODO(fbarchard): Port MJpeg to C.
   MJpegDecoder mjpeg_decoder;
-  LIBYUV_BOOL ret = mjpeg_decoder.LoadFrame(sample, sample_size);
+  LIBYUV_BOOL ret = mjpeg_decoder.LoadFrame(src_mjpg, src_size_mjpg);
   if (ret && (mjpeg_decoder.GetWidth() != src_width ||
               mjpeg_decoder.GetHeight() != src_height)) {
     // ERROR: MJPEG frame has unexpected dimensions
@@ -450,9 +450,9 @@ int MJPGToARGB(const uint8_t* sample,
       ret = mjpeg_decoder.DecodeToCallback(&JpegI400ToARGB, &bufs, dst_width,
                                            dst_height);
     } else {
-      // TODO(fbarchard): Implement conversion for any other colorspace/sample
-      // factors that occur in practice.
-      // ERROR: Unable to convert MJPEG frame because format is not supported
+      // TODO(fbarchard): Implement conversion for any other
+      // colorspace/subsample factors that occur in practice. ERROR: Unable to
+      // convert MJPEG frame because format is not supported
       mjpeg_decoder.UnloadFrame();
       return 1;
     }

source/mjpeg_validate.cc

@@ -18,10 +18,10 @@ extern "C" {
 #endif
 
 // Helper function to scan for EOI marker (0xff 0xd9).
-static LIBYUV_BOOL ScanEOI(const uint8_t* sample, size_t sample_size) {
-  if (sample_size >= 2) {
-    const uint8_t* end = sample + sample_size - 1;
-    const uint8_t* it = sample;
+static LIBYUV_BOOL ScanEOI(const uint8_t* src_mjpg, size_t src_size_mjpg) {
+  if (src_size_mjpg >= 2) {
+    const uint8_t* end = src_mjpg + src_size_mjpg - 1;
+    const uint8_t* it = src_mjpg;
     while (it < end) {
       // TODO(fbarchard): scan for 0xd9 instead.
       it = (const uint8_t*)(memchr(it, 0xff, end - it));
@@ -34,34 +34,34 @@ static LIBYUV_BOOL ScanEOI(const uint8_t* sample, size_t sample_size) {
       ++it;  // Skip over current 0xff.
     }
   }
-  // ERROR: Invalid jpeg end code not found. Size sample_size
+  // ERROR: Invalid jpeg end code not found. Size src_size_mjpg
   return LIBYUV_FALSE;
 }
 
 // Helper function to validate the jpeg appears intact.
-LIBYUV_BOOL ValidateJpeg(const uint8_t* sample, size_t sample_size) {
+LIBYUV_BOOL ValidateJpeg(const uint8_t* src_mjpg, size_t src_size_mjpg) {
   // Maximum size that ValidateJpeg will consider valid.
   const size_t kMaxJpegSize = 0x7fffffffull;
   const size_t kBackSearchSize = 1024;
-  if (sample_size < 64 || sample_size > kMaxJpegSize || !sample) {
-    // ERROR: Invalid jpeg size: sample_size
+  if (src_size_mjpg < 64 || src_size_mjpg > kMaxJpegSize || !src_mjpg) {
+    // ERROR: Invalid jpeg size: src_size_mjpg
     return LIBYUV_FALSE;
   }
-  if (sample[0] != 0xff || sample[1] != 0xd8) {  // SOI marker
+  if (src_mjpg[0] != 0xff || src_mjpg[1] != 0xd8) {  // SOI marker
     // ERROR: Invalid jpeg initial start code
     return LIBYUV_FALSE;
   }
 
   // Look for the End Of Image (EOI) marker near the end of the buffer.
-  if (sample_size > kBackSearchSize) {
-    if (ScanEOI(sample + sample_size - kBackSearchSize, kBackSearchSize)) {
+  if (src_size_mjpg > kBackSearchSize) {
+    if (ScanEOI(src_mjpg + src_size_mjpg - kBackSearchSize, kBackSearchSize)) {
       return LIBYUV_TRUE;  // Success: Valid jpeg.
     }
     // Reduce search size for forward search.
-    sample_size = sample_size - kBackSearchSize + 1;
+    src_size_mjpg = src_size_mjpg - kBackSearchSize + 1;
   }
   // Step over SOI marker and scan for EOI.
-  return ScanEOI(sample + 2, sample_size - 2);
+  return ScanEOI(src_mjpg + 2, src_size_mjpg - 2);
 }
 
 #ifdef __cplusplus

source/scale_mmi.cc

@@ -26,6 +26,8 @@ extern "C" {
 // This module is for Mips MMI.
 #if !defined(LIBYUV_DISABLE_MMI) && defined(_MIPS_ARCH_LOONGSON3A)
 
+// clang-format off
+
 // CPU agnostic row functions
 void ScaleRowDown2_MMI(const uint8_t* src_ptr,
                        ptrdiff_t src_stride,
@@ -1101,6 +1103,8 @@ void ScaleRowUp2_16_MMI(const uint16_t* src_ptr,
       : "memory");
 }
 
+// clang-format on
+
 #endif  // !defined(LIBYUV_DISABLE_MMI) && defined(_MIPS_ARCH_LOONGSON3A)
 
 #ifdef __cplusplus