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comparison: media/libvpx/vp9/encoder/vp9_boolhuff.h
media/libvpx/vp9/encoder/vp9_boolhuff.h
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- TOR_BUG_9701
- changeset 15
- b8a032363ba2
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| -1:000000000000 | 0:8c5895fbd03d |
|---|---|
| 1 /* | |
| 2 * Copyright (c) 2010 The WebM project authors. All Rights Reserved. | |
| 3 * | |
| 4 * Use of this source code is governed by a BSD-style license | |
| 5 * that can be found in the LICENSE file in the root of the source | |
| 6 * tree. An additional intellectual property rights grant can be found | |
| 7 * in the file PATENTS. All contributing project authors may | |
| 8 * be found in the AUTHORS file in the root of the source tree. | |
| 9 */ | |
| 10 | |
| 11 | |
| 12 /**************************************************************************** | |
| 13 * | |
| 14 * Module Title : vp9_boolhuff.h | |
| 15 * | |
| 16 * Description : Bool Coder header file. | |
| 17 * | |
| 18 ****************************************************************************/ | |
| 19 #ifndef VP9_ENCODER_VP9_BOOLHUFF_H_ | |
| 20 #define VP9_ENCODER_VP9_BOOLHUFF_H_ | |
| 21 | |
| 22 #include "vpx_ports/mem.h" | |
| 23 | |
| 24 typedef struct { | |
| 25 unsigned int lowvalue; | |
| 26 unsigned int range; | |
| 27 unsigned int value; | |
| 28 int count; | |
| 29 unsigned int pos; | |
| 30 uint8_t *buffer; | |
| 31 | |
| 32 // Variables used to track bit costs without outputing to the bitstream | |
| 33 unsigned int measure_cost; | |
| 34 unsigned long bit_counter; | |
| 35 } vp9_writer; | |
| 36 | |
| 37 extern const unsigned int vp9_prob_cost[256]; | |
| 38 | |
| 39 void vp9_start_encode(vp9_writer *bc, uint8_t *buffer); | |
| 40 void vp9_stop_encode(vp9_writer *bc); | |
| 41 | |
| 42 DECLARE_ALIGNED(16, extern const unsigned char, vp9_norm[256]); | |
| 43 | |
| 44 static void vp9_write(vp9_writer *br, int bit, int probability) { | |
| 45 unsigned int split; | |
| 46 int count = br->count; | |
| 47 unsigned int range = br->range; | |
| 48 unsigned int lowvalue = br->lowvalue; | |
| 49 register unsigned int shift; | |
| 50 | |
| 51 #ifdef ENTROPY_STATS | |
| 52 #if defined(SECTIONBITS_OUTPUT) | |
| 53 | |
| 54 if (bit) | |
| 55 Sectionbits[active_section] += vp9_prob_cost[255 - probability]; | |
| 56 else | |
| 57 Sectionbits[active_section] += vp9_prob_cost[probability]; | |
| 58 | |
| 59 #endif | |
| 60 #endif | |
| 61 | |
| 62 split = 1 + (((range - 1) * probability) >> 8); | |
| 63 | |
| 64 range = split; | |
| 65 | |
| 66 if (bit) { | |
| 67 lowvalue += split; | |
| 68 range = br->range - split; | |
| 69 } | |
| 70 | |
| 71 shift = vp9_norm[range]; | |
| 72 | |
| 73 range <<= shift; | |
| 74 count += shift; | |
| 75 | |
| 76 if (count >= 0) { | |
| 77 int offset = shift - count; | |
| 78 | |
| 79 if ((lowvalue << (offset - 1)) & 0x80000000) { | |
| 80 int x = br->pos - 1; | |
| 81 | |
| 82 while (x >= 0 && br->buffer[x] == 0xff) { | |
| 83 br->buffer[x] = 0; | |
| 84 x--; | |
| 85 } | |
| 86 | |
| 87 br->buffer[x] += 1; | |
| 88 } | |
| 89 | |
| 90 br->buffer[br->pos++] = (lowvalue >> (24 - offset)); | |
| 91 lowvalue <<= offset; | |
| 92 shift = count; | |
| 93 lowvalue &= 0xffffff; | |
| 94 count -= 8; | |
| 95 } | |
| 96 | |
| 97 lowvalue <<= shift; | |
| 98 br->count = count; | |
| 99 br->lowvalue = lowvalue; | |
| 100 br->range = range; | |
| 101 } | |
| 102 | |
| 103 static void vp9_write_bit(vp9_writer *w, int bit) { | |
| 104 vp9_write(w, bit, 128); // vp9_prob_half | |
| 105 } | |
| 106 | |
| 107 static void vp9_write_literal(vp9_writer *w, int data, int bits) { | |
| 108 int bit; | |
| 109 | |
| 110 for (bit = bits - 1; bit >= 0; bit--) | |
| 111 vp9_write_bit(w, 1 & (data >> bit)); | |
| 112 } | |
| 113 | |
| 114 | |
| 115 #endif // VP9_ENCODER_VP9_BOOLHUFF_H_ |
