diff options
Diffstat (limited to 'webrtc/modules/video_coding/utility/vp8_header_parser.h')
-rw-r--r-- | webrtc/modules/video_coding/utility/vp8_header_parser.h | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/webrtc/modules/video_coding/utility/vp8_header_parser.h b/webrtc/modules/video_coding/utility/vp8_header_parser.h new file mode 100644 index 0000000000..b0c684c578 --- /dev/null +++ b/webrtc/modules/video_coding/utility/vp8_header_parser.h @@ -0,0 +1,68 @@ +/* + * Copyright (c) 2015 The WebRTC project authors. All Rights Reserved. + * + * Use of this source code is governed by a BSD-style license + * that can be found in the LICENSE file in the root of the source + * tree. An additional intellectual property rights grant can be found + * in the file PATENTS. All contributing project authors may + * be found in the AUTHORS file in the root of the source tree. + */ + +#ifndef WEBRTC_MODULES_VIDEO_CODING_UTILITY_VP8_HEADER_PARSER_H_ +#define WEBRTC_MODULES_VIDEO_CODING_UTILITY_VP8_HEADER_PARSER_H_ + +#include <stdint.h> +#include <stdio.h> + +namespace webrtc { + +namespace vp8 { + +enum { + MB_FEATURE_TREE_PROBS = 3, + NUM_MB_SEGMENTS = 4, + NUM_REF_LF_DELTAS = 4, + NUM_MODE_LF_DELTAS = 4, +}; + +typedef struct VP8BitReader VP8BitReader; +struct VP8BitReader { + // Boolean decoder. + uint32_t value_; // Current value. + uint32_t range_; // Current range minus 1. In [127, 254] interval. + int bits_; // Number of valid bits left. + // Read buffer. + const uint8_t* buf_; // Next byte to be read. + const uint8_t* buf_end_; // End of read buffer. + int eof_; // True if input is exhausted. +}; + +const uint8_t kVP8Log2Range[128] = { + 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4, 3, 3, 3, 3, 3, 3, 3, + 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, + 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0}; + +// range = ((range - 1) << kVP8Log2Range[range]) + 1 +const uint8_t kVP8NewRange[128] = { + 127, 127, 191, 127, 159, 191, 223, 127, 143, 159, 175, 191, 207, 223, 239, + 127, 135, 143, 151, 159, 167, 175, 183, 191, 199, 207, 215, 223, 231, 239, + 247, 127, 131, 135, 139, 143, 147, 151, 155, 159, 163, 167, 171, 175, 179, + 183, 187, 191, 195, 199, 203, 207, 211, 215, 219, 223, 227, 231, 235, 239, + 243, 247, 251, 127, 129, 131, 133, 135, 137, 139, 141, 143, 145, 147, 149, + 151, 153, 155, 157, 159, 161, 163, 165, 167, 169, 171, 173, 175, 177, 179, + 181, 183, 185, 187, 189, 191, 193, 195, 197, 199, 201, 203, 205, 207, 209, + 211, 213, 215, 217, 219, 221, 223, 225, 227, 229, 231, 233, 235, 237, 239, + 241, 243, 245, 247, 249, 251, 253, 127}; + +// Gets the QP, QP range: [0, 127]. +// Returns true on success, false otherwise. +bool GetQp(const uint8_t* buf, size_t length, int* qp); + +} // namespace vp8 + +} // namespace webrtc + +#endif // WEBRTC_MODULES_VIDEO_CODING_UTILITY_VP8_HEADER_PARSER_H_ |