File video capture device supports MJPEG format

media/filters/jpeg_parser.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 #ifndef MEDIA_FILTERS_JPEG_PARSER_H_
 #define MEDIA_FILTERS_JPEG_PARSER_H_
 
 #include <stddef.h>
 #include <stdint.h>
 #include "media/base/media_export.h"
@@ skipping 12 matching lines @@
   JPEG_SOF10 = 0xCA,  // start of frame (arithmetic coding, progressive)
   JPEG_SOF11 = 0xCB,  // start of frame (arithmetic coding, lossless)
   JPEG_SOF13 = 0xCD,  // start of frame (differential, arithmetic, sequential)
   JPEG_SOF14 = 0xCE,  // start of frame (differential, arithmetic, progressive)
   JPEG_SOF15 = 0xCF,  // start of frame (differential, arithmetic, lossless)
   JPEG_DHT = 0xC4,    // define huffman table
   JPEG_SOI = 0xD8,    // start of image
   JPEG_SOS = 0xDA,    // start of scan
   JPEG_DQT = 0xDB,    // define quantization table
   JPEG_DRI = 0xDD,    // define restart internal
+  JPEG_RST0 = 0xD0,   // restart
+  JPEG_RST1 = 0xD1,   // restart
+  JPEG_RST2 = 0xD2,   // restart
+  JPEG_RST3 = 0xD3,   // restart
+  JPEG_RST4 = 0xD4,   // restart
+  JPEG_RST5 = 0xD5,   // restart
+  JPEG_RST6 = 0xD6,   // restart
+  JPEG_RST7 = 0xD7,   // restart
+  JPEG_EOI = 0xD9,    // end of image

[xhwang, 2015/08/18 17:17:55]

Can we order these by value?

[henryhsu, 2015/08/19 10:05:12]

Done.

   JPEG_MARKER_PREFIX = 0xFF,  // jpeg marker prefix
 };
 
 const size_t kJpegMaxHuffmanTableNumBaseline = 2;
 const size_t kJpegMaxComponents = 4;
 const size_t kJpegMaxQuantizationTableNum = 4;
 
 // Parsing result of JPEG DHT marker.
 struct JpegHuffmanTable {
   bool valid;
@@ skipping 35 matching lines @@
   } components[kJpegMaxComponents];
 };
 
 struct JpegParseResult {
   JpegFrameHeader frame_header;
   JpegHuffmanTable dc_table[kJpegMaxHuffmanTableNumBaseline];
   JpegHuffmanTable ac_table[kJpegMaxHuffmanTableNumBaseline];
   JpegQuantizationTable q_table[kJpegMaxQuantizationTableNum];
   uint16_t restart_interval;
   JpegScanHeader scan;
   const char* data;

[xhwang, 2015/08/18 17:17:55]

Is this for the whole compressed data?

[henryhsu, 2015/08/19 01:57:24]

Yes. But only for one image.

+  // The size of compressed data.
   size_t data_size;
+  // The size of entire image including header.
+  size_t image_size;
 };
 
 // Parses JPEG picture in |buffer| with |length|.  Returns true iff header is
 // valid and JPEG baseline sequential process is present. If parsed
 // successfully, |result| is the parsed result.
 // It's not a full featured JPEG parser implememtation. It only parses JPEG
 // baseline sequential process. For explanations of each struct and its
 // members, see JPEG specification at
 // http://www.w3.org/Graphics/JPEG/itu-t81.pdf.
 MEDIA_EXPORT bool ParseJpegPicture(const uint8_t* buffer,
                                    size_t length,
                                    JpegParseResult* result);
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_JPEG_PARSER_H_