FFmpeg: libavcodec/ffv1.c Source File

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libavcodec

ffv1.c

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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 /**

24 * @file

25 * FF Video Codec 1 (a lossless codec)

26 */

28 #include "libavutil/attributes.h"

29 #include "libavutil/avassert.h"

30 #include "libavutil/crc.h"

31 #include "libavutil/opt.h"

32 #include "libavutil/imgutils.h"

33 #include "libavutil/pixdesc.h"

34 #include "libavutil/timer.h"

35 #include "avcodec.h"

36 #include "internal.h"

37 #include "rangecoder.h"

38 #include "golomb.h"

39 #include "mathops.h"

40 #include "ffv1.h"

42 av_cold int ffv1_common_init(AVCodecContext *avctx)

43 {

44 FFV1Context *s = avctx->priv_data;

46 if (!avctx->width || !avctx->height)

47 return AVERROR_INVALIDDATA;

49 s->avctx = avctx;

50 s->flags = avctx->flags;

52 s->picture.f = av_frame_alloc();

53 s->last_picture.f = av_frame_alloc();

54 if (!s->picture.f || !s->last_picture.f)

55 return AVERROR(ENOMEM);

57 s->width = avctx->width;

58 s->height = avctx->height;

60 // defaults

61 s->num_h_slices = 1;

62 s->num_v_slices = 1;

64 return 0;

65 }

67 av_cold int ffv1_init_slice_state(FFV1Context *f, FFV1Context *fs)

68 {

69 int j;

71 fs->plane_count = f->plane_count;

72 fs->transparency = f->transparency;

73 for (j = 0; j < f->plane_count; j++) {

74 PlaneContext *const p = &fs->plane[j];

76 if (fs->ac) {

77 if (!p->state)

78 p->state = av_malloc_array(p->context_count, CONTEXT_SIZE *

79 sizeof(uint8_t));

80 if (!p->state)

81 return AVERROR(ENOMEM);

82 } else {

83 if (!p->vlc_state)

84 p->vlc_state = av_malloc_array(p->context_count, sizeof(VlcState));

85 if (!p->vlc_state)

86 return AVERROR(ENOMEM);

87 }

88 }

90 if (fs->ac > 1) {

91 //FIXME only redo if state_transition changed

92 for (j = 1; j < 256; j++) {

93 fs->c. one_state[ j] = f->state_transition[j];

94 fs->c.zero_state[256 - j] = 256 - fs->c.one_state[j];

95 }

96 }

98 return 0;

99 }

100

101 av_cold int ffv1_init_slices_state(FFV1Context *f)

102 {

103 int i, ret;

104 for (i = 0; i < f->slice_count; i++) {

105 FFV1Context *fs = f->slice_context[i];

106 if ((ret = ffv1_init_slice_state(f, fs)) < 0)

107 return AVERROR(ENOMEM);

108 }

109 return 0;

110 }

111

112 av_cold int ffv1_init_slice_contexts(FFV1Context *f)

113 {

114 int i;

115

116 f->slice_count = f->num_h_slices * f->num_v_slices;

117 av_assert0(f->slice_count > 0);

118

119 for (i = 0; i < f->slice_count; i++) {

120 FFV1Context *fs = av_mallocz(sizeof(*fs));

121 int sx = i % f->num_h_slices;

122 int sy = i / f->num_h_slices;

123 int sxs = f->avctx->width * sx / f->num_h_slices;

124 int sxe = f->avctx->width * (sx + 1) / f->num_h_slices;

125 int sys = f->avctx->height * sy / f->num_v_slices;

126 int sye = f->avctx->height * (sy + 1) / f->num_v_slices;

127

128 if (!fs)

129 return AVERROR(ENOMEM);

130

131 f->slice_context[i] = fs;

132 memcpy(fs, f, sizeof(*fs));

133 memset(fs->rc_stat2, 0, sizeof(fs->rc_stat2));

134

135 fs->slice_width = sxe - sxs;

136 fs->slice_height = sye - sys;

137 fs->slice_x = sxs;

138 fs->slice_y = sys;

139

140 fs->sample_buffer = av_malloc_array((fs->width + 6), 3 * MAX_PLANES *

141 sizeof(*fs->sample_buffer));

142 if (!fs->sample_buffer)

143 return AVERROR(ENOMEM);

144 }

145 return 0;

146 }

147

148 int ffv1_allocate_initial_states(FFV1Context *f)

149 {

150 int i;

151

152 for (i = 0; i < f->quant_table_count; i++) {

153 f->initial_states[i] = av_malloc_array(f->context_count[i],

154 sizeof(*f->initial_states[i]));

155 if (!f->initial_states[i])

156 return AVERROR(ENOMEM);

157 memset(f->initial_states[i], 128,

158 f->context_count[i] * sizeof(*f->initial_states[i]));

159 }

160 return 0;

161 }

162

163 void ffv1_clear_slice_state(FFV1Context *f, FFV1Context *fs)

164 {

165 int i, j;

166

167 for (i = 0; i < f->plane_count; i++) {

168 PlaneContext *p = &fs->plane[i];

169

170 p->interlace_bit_state[0] = 128;

171 p->interlace_bit_state[1] = 128;

172

173 if (fs->ac) {

174 if (f->initial_states[p->quant_table_index]) {

175 memcpy(p->state, f->initial_states[p->quant_table_index],

176 CONTEXT_SIZE * p->context_count);

177 } else

178 memset(p->state, 128, CONTEXT_SIZE * p->context_count);

179 } else {

180 for (j = 0; j < p->context_count; j++) {

181 p->vlc_state[j].drift = 0;

182 p->vlc_state[j].error_sum = 4; //FFMAX((RANGE + 32)/64, 2);

183 p->vlc_state[j].bias = 0;

184 p->vlc_state[j].count = 1;

185 }

186 }

187 }

188 }

189

190

191 av_cold int ffv1_close(AVCodecContext *avctx)

192 {

193 FFV1Context *s = avctx->priv_data;

194 int i, j;

195

196 if (s->picture.f)

197 ff_thread_release_buffer(avctx, &s->picture);

198 av_frame_free(&s->picture.f);

199

200 if (s->last_picture.f)

201 ff_thread_release_buffer(avctx, &s->last_picture);

202 av_frame_free(&s->last_picture.f);

203

204 for (j = 0; j < s->slice_count; j++) {

205 FFV1Context *fs = s->slice_context[j];

206 for (i = 0; i < s->plane_count; i++) {

207 PlaneContext *p = &fs->plane[i];

208

209 av_freep(&p->state);

210 av_freep(&p->vlc_state);

211 }

212 av_freep(&fs->sample_buffer);

213 }

214

215 av_freep(&avctx->stats_out);

216 for (j = 0; j < s->quant_table_count; j++) {

217 av_freep(&s->initial_states[j]);

218 for (i = 0; i < s->slice_count; i++) {

219 FFV1Context *sf = s->slice_context[i];

220 av_freep(&sf->rc_stat2[j]);

221 }

222 av_freep(&s->rc_stat2[j]);

223 }

224

225 for (i = 0; i < s->slice_count; i++)

226 av_freep(&s->slice_context[i]);

227

228 return 0;

229 }

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