Add JPEG parser for JPEG decode acceleration

media/filters/jpeg_parser.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.

[xhwang, 2015/01/12 18:08:57]

2015

[kcwu, 2015/01/13 14:57:00]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "media/filters/jpeg_parser.h"
+
+#include "base/big_endian.h"
+#include "base/logging.h"
+
+using base::BigEndianReader;
+
+#define READ_U8_OR_RETURN_FALSE(out)                                       \
+  do {                                                                     \
+    uint8_t _out;                                                          \
+    if (!reader.ReadU8(&_out)) {                                           \
+      DVLOG(1)                                                             \
+          << "Error in stream: unexpected EOS while trying to read " #out; \
+      return false;                                                        \
+    }                                                                      \
+    *(out) = _out;                                                         \
+  } while (0)
+
+#define READ_U16_OR_RETURN_FALSE(out)                                      \
+  do {                                                                     \
+    uint16_t _out;                                                         \
+    if (!reader.ReadU16(&_out)) {                                          \
+      DVLOG(1)                                                             \
+          << "Error in stream: unexpected EOS while trying to read " #out; \
+      return false;                                                        \
+    }                                                                      \
+    *(out) = _out;                                                         \
+  } while (0)
+
+#define IN_RANGE_OR_RETURN_FALSE(val, min, max)                             \

[xhwang, 2015/01/12 18:08:57]

We don't like to overuse macros. Can we just have a range check function
InRange(), and then in the caller, have something like:

if (!InRange(...))
  return false;

?

[kcwu, 2015/01/13 14:57:00]

Done.

+  do {                                                                      \
+    if ((val) < (min) || (val) > (max)) {                                   \
+      DVLOG(1) << "Error in stream: invalid value, expected " #val " to be" \
+               << " in range [" << (min) << ":" << (max) << "]"             \
+               << " found " << (val) << " instead";                         \
+      return false;                                                         \
+    }                                                                       \
+  } while (0)
+
+namespace media {
+
+namespace {
+enum JpegMarker {
+  SOF0 = 0xC0,     // start of frame (baseline)
+  DHT = 0xC4,      // define huffman table
+  SOI = 0xD8,      // start of image
+  SOS = 0xDA,      // start of scan
+  DQT = 0xDB,      // define quantization table
+  DRI = 0xDD,      // define restart internal
+  MARKER1 = 0xFF,  // jpeg marker prefix
+};
+}  // namespace
+
+bool JpegParser::Parse(const uint8_t* buffer,
+                       size_t length,
+                       JpegParseResult* result) {
+  DCHECK(buffer);
+  DCHECK(result);
+  BigEndianReader reader(reinterpret_cast<const char*>(buffer), length);
+  memset(result, 0, sizeof(JpegParseResult));
+
+  uint8_t marker1, marker2;
+  READ_U8_OR_RETURN_FALSE(&marker1);
+  READ_U8_OR_RETURN_FALSE(&marker2);
+  if (marker1 != MARKER1 || marker2 != SOI) {
+    DLOG(ERROR) << "Not a JPEG";
+    return false;
+  }
+
+  return ParseSOI(reader.ptr(), reader.remaining(), result);
+}
+

[xhwang, 2015/01/12 18:08:57]

Can you move the definition of ParseSOI() closer to Parse()? IMHO the
readability is better that way.

[kcwu, 2015/01/13 14:57:00]

Done.

+bool JpegParser::ParseSOF(const char* buffer,
+                          size_t length,
+                          JpegParseResult* result) {

[xhwang, 2015/01/12 18:08:58]

Here and below, can we make the output of these functions more specific. For
example, this function only reads the |num_components|, |components|,
|visible_height| and |visible_width|.

[kcwu, 2015/01/13 14:57:00]

Done.

+  // Spec B.2.2 Frame header syntax
+  DCHECK(buffer);
+  DCHECK(result);
+  BigEndianReader reader(buffer, length);
+
+  uint8_t precision;
+  READ_U8_OR_RETURN_FALSE(&precision);
+  READ_U16_OR_RETURN_FALSE(&result->visible_height);
+  READ_U16_OR_RETURN_FALSE(&result->visible_width);
+  READ_U8_OR_RETURN_FALSE(&result->num_components);
+
+  if (precision != 8) {
+    DLOG(ERROR) << "Only support 8-bit precision, not "
+                << static_cast<int>(precision) << " bit for baseline";
+    return false;
+  }
+  if (result->num_components >= arraysize(result->components)) {
+    DLOG(ERROR) << "num_components=" << static_cast<int>(result->num_components)
+                << " is not supported";
+    return false;
+  }
+
+  for (size_t i = 0; i < result->num_components; i++) {
+    JpegComponent& component = result->components[i];
+    READ_U8_OR_RETURN_FALSE(&component.id);
+    if (component.id > result->num_components) {
+      DLOG(ERROR) << "component id (" << static_cast<int>(component.id)
+                  << ") should be <= num_components ("
+                  << static_cast<int>(result->num_components) << ")";
+      return false;
+    }
+    uint8_t hv;
+    READ_U8_OR_RETURN_FALSE(&hv);
+    component.horizontal_sampling_factor = hv / 16;
+    component.vertical_sampling_factor = hv % 16;
+    IN_RANGE_OR_RETURN_FALSE(component.horizontal_sampling_factor, 1, 4);
+    IN_RANGE_OR_RETURN_FALSE(component.vertical_sampling_factor, 1, 4);
+    READ_U8_OR_RETURN_FALSE(&component.quantization_table_selector);
+  }
+
+  return true;
+}
+
+bool JpegParser::ParseDQT(const char* buffer,
+                          size_t length,
+                          JpegParseResult* result) {
+  // Spec B.2.4.1 Quantization table-specification syntax
+  DCHECK(buffer);
+  DCHECK(result);
+  BigEndianReader reader(buffer, length);
+  while (reader.remaining() > 0) {
+    uint8_t precision_and_table_id;
+    READ_U8_OR_RETURN_FALSE(&precision_and_table_id);
+    uint8_t precision = precision_and_table_id / 16;
+    uint8_t table_id = precision_and_table_id % 16;
+    IN_RANGE_OR_RETURN_FALSE(precision, 0, 1);
+    if (precision == 1) {  // 1 means 16-bit precision
+      DLOG(ERROR) << "An 8-bit DCT-based process shall not use a 16-bit "
+                  << "precision quantization table";
+      return false;
+    }
+    if (table_id >= kJpegMaxQuantizationTableNum) {
+      DLOG(ERROR) << "Quantization table id (" << static_cast<int>(table_id)
+                  << ") exceeded " << kJpegMaxQuantizationTableNum;
+      return false;
+    }
+
+    if (!reader.ReadBytes(&result->q_table[table_id].value,
+                          sizeof(result->q_table[table_id].value)))
+      return false;
+    result->q_table[table_id].valid = true;
+  }
+  return true;
+}
+
+bool JpegParser::ParseDHT(const char* buffer,
+                          size_t length,
+                          JpegParseResult* result) {
+  // Spec B.2.4.2 Huffman table-specification syntax
+  DCHECK(buffer);
+  DCHECK(result);
+  BigEndianReader reader(buffer, length);
+  while (reader.remaining() > 0) {
+    uint8_t table_class_and_id;
+    READ_U8_OR_RETURN_FALSE(&table_class_and_id);
+    int table_class = table_class_and_id / 16;
+    int table_id = table_class_and_id % 16;
+    IN_RANGE_OR_RETURN_FALSE(table_class, 0, 1);
+    if (table_id >= 2) {
+      DLOG(ERROR) << "Table id(" << table_id
+                  << ") >= 2 is invalid for baseline profile";
+      return false;
+    }
+
+    JpegHuffmanTable* table;
+    if (table_class == 1)
+      table = &result->ac_table[table_id];
+    else
+      table = &result->dc_table[table_id];
+
+    size_t count = 0;
+    if (!reader.ReadBytes(&table->code_length, sizeof(table->code_length)))
+      return false;
+    for (size_t i = 0; i < arraysize(table->code_length); i++)
+      count += table->code_length[i];
+
+    IN_RANGE_OR_RETURN_FALSE(count, 0, sizeof(table->code_value));
+    if (!reader.ReadBytes(&table->code_value, count))
+      return false;
+    table->valid = true;
+  }
+  return true;
+}
+
+bool JpegParser::ParseDRI(const char* buffer,
+                          size_t length,
+                          JpegParseResult* result) {
+  // Spec B.2.4.4 Restart interval definition syntax
+  DCHECK(buffer);
+  DCHECK(result);
+  BigEndianReader reader(buffer, length);
+  return reader.ReadU16(&result->restart_interval) && reader.remaining() == 0;
+}
+
+bool JpegParser::ParseSOS(const char* buffer,
+                          size_t length,
+                          JpegParseResult* result) {
+  // Spec B.2.3 Scan header syntax
+  DCHECK(buffer);
+  DCHECK(result);
+  BigEndianReader reader(buffer, length);
+  READ_U8_OR_RETURN_FALSE(&result->scan.num_components);
+  if (result->scan.num_components != result->num_components) {
+    DLOG(ERROR) << "The number of scan components ("
+                << static_cast<int>(result->scan.num_components)
+                << ") mismatches the number of image components ("
+                << static_cast<int>(result->num_components) << ")";
+    return false;
+  }
+
+  for (int i = 0; i < result->scan.num_components; i++) {
+    JpegScan::Component* component = &result->scan.components[i];
+    READ_U8_OR_RETURN_FALSE(&component->component_selector);
+    uint8_t dc_and_ac_selector;
+    READ_U8_OR_RETURN_FALSE(&dc_and_ac_selector);
+    component->dc_selector = dc_and_ac_selector / 16;
+    component->ac_selector = dc_and_ac_selector % 16;
+    if (component->component_selector != result->components[i].id) {
+      DLOG(ERROR) << "component selector mismatches image component id";
+      return false;
+    }
+    if (component->dc_selector >= kJpegMaxHuffmanTableNum_baseline) {
+      DLOG(ERROR) << "DC selector (" << static_cast<int>(component->dc_selector)
+                  << ") should be 0 or 1 for baseline mode";
+      return false;
+    }
+    if (component->ac_selector >= kJpegMaxHuffmanTableNum_baseline) {
+      DLOG(ERROR) << "AC selector (" << static_cast<int>(component->ac_selector)
+                  << ") should be 0 or 1 for baseline mode";
+      return false;
+    }
+  }
+
+  // Unused fields, only for value checking.
+  uint8_t spectral_selection_start;
+  uint8_t spectral_selection_end;
+  uint8_t point_transform;
+  READ_U8_OR_RETURN_FALSE(&spectral_selection_start);
+  READ_U8_OR_RETURN_FALSE(&spectral_selection_end);
+  READ_U8_OR_RETURN_FALSE(&point_transform);
+  if (spectral_selection_start != 0 || spectral_selection_end != 63) {
+    DLOG(ERROR) << "Spectral selection should be 0,63 for baseline mode";
+    return false;
+  }
+  if (point_transform != 0) {
+    DLOG(ERROR) << "Point transform should be 0 for baseline mode";
+    return false;
+  }
+
+  return true;
+}
+
+bool JpegParser::ParseSOI(const char* buffer,
+                          size_t length,
+                          JpegParseResult* result) {
+  // Spec B.2.1 High-level syntax
+  DCHECK(buffer);
+  DCHECK(result);
+  BigEndianReader reader(buffer, length);
+  uint8_t marker1;
+  uint8_t marker2;
+  bool has_marker_dqt = false;
+  bool has_marker_sos = false;
+
+  // Once reached SOS, all neccesary data are parsed.
+  while (!has_marker_sos) {
+    READ_U8_OR_RETURN_FALSE(&marker1);
+    if (marker1 != MARKER1)
+      return false;
+
+    do {
+      READ_U8_OR_RETURN_FALSE(&marker2);
+    } while (marker2 == MARKER1);  // skip fill bytes
+
+    uint16_t size;
+    READ_U16_OR_RETURN_FALSE(&size);
+    if (reader.remaining() < size) {
+      DLOG(ERROR) << "Ill-formed JPEG. Remaining size (" << reader.remaining()
+                  << ") is smaller than header specified (" << size << ")";
+      return false;
+    }
+
+    // The size includes the size field itself.
+    if (size < sizeof(size)) {
+      DLOG(ERROR) << "Ill-formed JPEG. Segment size (" << size
+                  << ") is smaller than size field (" << sizeof(size) << ")";
+      return false;
+    }
+    size -= sizeof(size);
+
+    switch (marker2) {
+      case SOF0:
+        if (!ParseSOF(reader.ptr(), size, result)) {
+          DLOG(ERROR) << "ParseSOF failed";
+          return false;
+        }
+        break;
+      case DQT:
+        if (!ParseDQT(reader.ptr(), size, result)) {
+          DLOG(ERROR) << "ParseDQT failed";
+          return false;
+        }
+        has_marker_dqt = true;
+        break;
+      case DHT:
+        if (!ParseDHT(reader.ptr(), size, result)) {
+          DLOG(ERROR) << "ParseDHT failed";
+          return false;
+        }
+        break;
+      case DRI:
+        if (!ParseDRI(reader.ptr(), size, result)) {
+          DLOG(ERROR) << "ParseDRI failed";
+          return false;
+        }
+        break;
+      case SOS:
+        if (!ParseSOS(reader.ptr(), size, result)) {
+          DLOG(ERROR) << "ParseSOS failed";
+          return false;
+        }
+        has_marker_sos = true;
+        break;
+      default:
+        DVLOG(4) << "unknown marker " << static_cast<int>(marker2);
+        break;
+    }
+    reader.Skip(size);
+  }
+
+  if (!has_marker_dqt) {
+    DLOG(ERROR) << "No DQT marker found";
+    return false;
+  }
+
+  // Scan data follows scan header immediately.
+  result->scan.data = reader.ptr();
+  result->scan.data_size = reader.remaining();
+
+  return true;
+}
+
+}  // namespace media