diff options
Diffstat (limited to 'media/libvpx/vp8/encoder/boolhuff.h')
-rw-r--r-- | media/libvpx/vp8/encoder/boolhuff.h | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/media/libvpx/vp8/encoder/boolhuff.h b/media/libvpx/vp8/encoder/boolhuff.h new file mode 100644 index 000000000..7c012a829 --- /dev/null +++ b/media/libvpx/vp8/encoder/boolhuff.h @@ -0,0 +1,132 @@ +/* + * Copyright (c) 2010 The WebM 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. + */ + + +/**************************************************************************** +* +* Module Title : boolhuff.h +* +* Description : Bool Coder header file. +* +****************************************************************************/ +#ifndef VP8_ENCODER_BOOLHUFF_H_ +#define VP8_ENCODER_BOOLHUFF_H_ + +#include "vpx_ports/mem.h" +#include "vpx/internal/vpx_codec_internal.h" + +#ifdef __cplusplus +extern "C" { +#endif + +typedef struct +{ + unsigned int lowvalue; + unsigned int range; + int count; + unsigned int pos; + unsigned char *buffer; + unsigned char *buffer_end; + struct vpx_internal_error_info *error; +} BOOL_CODER; + +extern void vp8_start_encode(BOOL_CODER *bc, unsigned char *buffer, unsigned char *buffer_end); + +extern void vp8_encode_value(BOOL_CODER *br, int data, int bits); +extern void vp8_stop_encode(BOOL_CODER *bc); +extern const unsigned int vp8_prob_cost[256]; + + +DECLARE_ALIGNED(16, extern const unsigned char, vp8_norm[256]); + +static int validate_buffer(const unsigned char *start, + size_t len, + const unsigned char *end, + struct vpx_internal_error_info *error) +{ + if (start + len > start && start + len < end) + return 1; + else + vpx_internal_error(error, VPX_CODEC_CORRUPT_FRAME, + "Truncated packet or corrupt partition "); + + return 0; +} +static void vp8_encode_bool(BOOL_CODER *br, int bit, int probability) +{ + unsigned int split; + int count = br->count; + unsigned int range = br->range; + unsigned int lowvalue = br->lowvalue; + register unsigned int shift; + +#ifdef VP8_ENTROPY_STATS +#if defined(SECTIONBITS_OUTPUT) + + if (bit) + Sectionbits[active_section] += vp8_prob_cost[255-probability]; + else + Sectionbits[active_section] += vp8_prob_cost[probability]; + +#endif +#endif + + split = 1 + (((range - 1) * probability) >> 8); + + range = split; + + if (bit) + { + lowvalue += split; + range = br->range - split; + } + + shift = vp8_norm[range]; + + range <<= shift; + count += shift; + + if (count >= 0) + { + int offset = shift - count; + + if ((lowvalue << (offset - 1)) & 0x80000000) + { + int x = br->pos - 1; + + while (x >= 0 && br->buffer[x] == 0xff) + { + br->buffer[x] = (unsigned char)0; + x--; + } + + br->buffer[x] += 1; + } + + validate_buffer(br->buffer + br->pos, 1, br->buffer_end, br->error); + br->buffer[br->pos++] = (lowvalue >> (24 - offset)); + + lowvalue <<= offset; + shift = count; + lowvalue &= 0xffffff; + count -= 8 ; + } + + lowvalue <<= shift; + br->count = count; + br->lowvalue = lowvalue; + br->range = range; +} + +#ifdef __cplusplus +} // extern "C" +#endif + +#endif // VP8_ENCODER_BOOLHUFF_H_ |