FFmpeg: libavcodec/ffv1.h Source File

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libavcodec

ffv1.h

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1 /*

2 * FFV1 codec for libavcodec

3 *

5 *

6 * This file is part of FFmpeg.

7 *

8 * FFmpeg is free software; you can redistribute it and/or

9 * modify it under the terms of the GNU Lesser General Public

10 * License as published by the Free Software Foundation; either

11 * version 2.1 of the License, or (at your option) any later version.

12 *

13 * FFmpeg is distributed in the hope that it will be useful,

14 * but WITHOUT ANY WARRANTY; without even the implied warranty of

15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

16 * Lesser General Public License for more details.

17 *

18 * You should have received a copy of the GNU Lesser General Public

19 * License along with FFmpeg; if not, write to the Free Software

20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

21 */

23 #ifndef AVCODEC_FFV1_H

24 #define AVCODEC_FFV1_H

26 /**

27 * @file

28 * FF Video Codec 1 (a lossless codec)

29 */

31 #include "libavutil/avassert.h"

32 #include "libavutil/crc.h"

33 #include "libavutil/opt.h"

34 #include "libavutil/imgutils.h"

35 #include "libavutil/pixdesc.h"

36 #include "libavutil/timer.h"

37 #include "avcodec.h"

38 #include "get_bits.h"

39 #include "internal.h"

40 #include "mathops.h"

41 #include "put_bits.h"

42 #include "rangecoder.h"

43 #include "thread.h"

45 #ifdef __INTEL_COMPILER

46 #undef av_flatten

47 #define av_flatten

48 #endif

50 #define MAX_PLANES 4

51 #define CONTEXT_SIZE 32

53 #define MAX_QUANT_TABLES 8

54 #define MAX_CONTEXT_INPUTS 5

56 typedef struct VlcState {

57 int16_t drift;

58 uint16_t error_sum;

59 int8_t bias;

60 uint8_t count;

61 } VlcState;

63 typedef struct PlaneContext {

64 int16_t quant_table[MAX_CONTEXT_INPUTS][256];

65 int quant_table_index;

66 int context_count;

67 uint8_t (*state)[CONTEXT_SIZE];

68 VlcState *vlc_state;

69 uint8_t interlace_bit_state[2];

70 } PlaneContext;

72 #define MAX_SLICES 256

74 typedef struct FFV1Context {

75 AVClass *class;

76 AVCodecContext *avctx;

77 RangeCoder c;

78 GetBitContext gb;

79 PutBitContext pb;

80 uint64_t rc_stat[256][2];

81 uint64_t (*rc_stat2[MAX_QUANT_TABLES])[32][2];

82 int version;

83 int micro_version;

84 int width, height;

85 int chroma_planes;

86 int chroma_h_shift, chroma_v_shift;

87 int transparency;

88 int flags;

89 int picture_number;

90 ThreadFrame picture, last_picture;

91 struct FFV1Context *fsrc;

93 AVFrame *cur;

94 int plane_count;

95 int ac; ///< 1=range coder <-> 0=golomb rice

96 int ac_byte_count; ///< number of bytes used for AC coding

97 PlaneContext plane[MAX_PLANES];

98 int16_t quant_table[MAX_CONTEXT_INPUTS][256];

99 int16_t quant_tables[MAX_QUANT_TABLES][MAX_CONTEXT_INPUTS][256];

100 int context_count[MAX_QUANT_TABLES];

101 uint8_t state_transition[256];

102 uint8_t (*initial_states[MAX_QUANT_TABLES])[32];

103 int run_index;

104 int colorspace;

105 int16_t *sample_buffer;

106

107 int ec;

108 int intra;

109 int slice_damaged;

110 int key_frame_ok;

111

112 int bits_per_raw_sample;

113 int packed_at_lsb;

114

115 int gob_count;

116 int quant_table_count;

117

118 struct FFV1Context *slice_context[MAX_SLICES];

119 int slice_count;

120 int num_v_slices;

121 int num_h_slices;

122 int slice_width;

123 int slice_height;

124 int slice_x;

125 int slice_y;

126 int slice_reset_contexts;

127 int slice_coding_mode;

128 int slice_rct_by_coef;

129 int slice_rct_ry_coef;

130 } FFV1Context;

131

132 int ffv1_common_init(AVCodecContext *avctx);

133 int ffv1_init_slice_state(FFV1Context *f, FFV1Context *fs);

134 int ffv1_init_slices_state(FFV1Context *f);

135 int ffv1_init_slice_contexts(FFV1Context *f);

136 int ffv1_allocate_initial_states(FFV1Context *f);

137 void ffv1_clear_slice_state(FFV1Context *f, FFV1Context *fs);

138 int ffv1_close(AVCodecContext *avctx);

139

140 static av_always_inline int fold(int diff, int bits)

141 {

142 if (bits == 8)

143 diff = (int8_t)diff;

144 else {

145 diff += 1 << (bits - 1);

146 diff &= (1 << bits) - 1;

147 diff -= 1 << (bits - 1);

148 }

149

150 return diff;

151 }

152

153 static inline int predict(int16_t *src, int16_t *last)

154 {

155 const int LT = last[-1];

156 const int T = last[0];

157 const int L = src[-1];

158

159 return mid_pred(L, L + T - LT, T);

160 }

161

162 static inline int get_context(PlaneContext *p, int16_t *src,

163 int16_t *last, int16_t *last2)

164 {

165 const int LT = last[-1];

166 const int T = last[0];

167 const int RT = last[1];

168 const int L = src[-1];

169

170 if (p->quant_table[3][127]) {

171 const int TT = last2[0];

172 const int LL = src[-2];

173 return p->quant_table[0][(L - LT) & 0xFF] +

174 p->quant_table[1][(LT - T) & 0xFF] +

175 p->quant_table[2][(T - RT) & 0xFF] +

176 p->quant_table[3][(LL - L) & 0xFF] +

177 p->quant_table[4][(TT - T) & 0xFF];

178 } else

179 return p->quant_table[0][(L - LT) & 0xFF] +

180 p->quant_table[1][(LT - T) & 0xFF] +

181 p->quant_table[2][(T - RT) & 0xFF];

182 }

183

184 static inline void update_vlc_state(VlcState *const state, const int v)

185 {

186 int drift = state->drift;

187 int count = state->count;

188 state->error_sum += FFABS(v);

189 drift += v;

190

191 if (count == 128) { // FIXME: variable

192 count >>= 1;

193 drift >>= 1;

194 state->error_sum >>= 1;

195 }

196 count++;

197

198 if (drift <= -count) {

199 if (state->bias > -128)

200 state->bias--;

201

202 drift += count;

203 if (drift <= -count)

204 drift = -count + 1;

205 } else if (drift > 0) {

206 if (state->bias < 127)

207 state->bias++;

208

209 drift -= count;

210 if (drift > 0)

211 drift = 0;

212 }

213

214 state->drift = drift;

215 state->count = count;

216 }

217

218 #endif /* AVCODEC_FFV1_H */

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