FFmpeg: libavcodec/indeo2.c Source File

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indeo2.c

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1 /*

2 * Intel Indeo 2 codec

4 *

5 * This file is part of FFmpeg.

6 *

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

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

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

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

11 *

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

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

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

15 * Lesser General Public License for more details.

16 *

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

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

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

20 */

22 /**

23 * @file

24 * Intel Indeo 2 decoder.

25 */

27 #include "libavutil/attributes.h"

28 #include "libavutil/thread.h"

30 #define BITSTREAM_READER_LE

31 #include "avcodec.h"

32 #include "get_bits.h"

33 #include "indeo2data.h"

34 #include "internal.h"

35 #include "mathops.h"

37 typedef struct Ir2Context{

38 AVCodecContext *avctx;

39 AVFrame *picture;

40 GetBitContext gb;

41 int decode_delta;

42 } Ir2Context;

44 #define CODE_VLC_BITS 14

45 static VLC ir2_vlc;

47 /* Indeo 2 codes are in range 0x01..0x7F and 0x81..0x90 */

48 static inline int ir2_get_code(GetBitContext *gb)

49 {

50 return get_vlc2(gb, ir2_vlc.table, CODE_VLC_BITS, 1);

51 }

53 static int ir2_decode_plane(Ir2Context *ctx, int width, int height, uint8_t *dst,

54 int pitch, const uint8_t *table)

55 {

56 int i;

57 int j;

58 int out = 0;

60 if ((width & 1) || width * height / (2*(IR2_CODES - 0x7F)) > get_bits_left(&ctx->gb))

61 return AVERROR_INVALIDDATA;

63 /* first line contain absolute values, other lines contain deltas */

64 while (out < width) {

65 int c = ir2_get_code(&ctx->gb);

66 if (c >= 0x80) { /* we have a run */

67 c -= 0x7F;

68 if (out + c*2 > width)

69 return AVERROR_INVALIDDATA;

70 for (i = 0; i < c * 2; i++)

71 dst[out++] = 0x80;

72 } else { /* copy two values from table */

73 if (c <= 0)

74 return AVERROR_INVALIDDATA;

75 dst[out++] = table[c * 2];

76 dst[out++] = table[(c * 2) + 1];

77 }

78 }

79 dst += pitch;

81 for (j = 1; j < height; j++) {

82 out = 0;

83 while (out < width) {

84 int c;

85 if (get_bits_left(&ctx->gb) <= 0)

86 return AVERROR_INVALIDDATA;

87 c = ir2_get_code(&ctx->gb);

88 if (c >= 0x80) { /* we have a skip */

89 c -= 0x7F;

90 if (out + c*2 > width)

91 return AVERROR_INVALIDDATA;

92 for (i = 0; i < c * 2; i++) {

93 dst[out] = dst[out - pitch];

94 out++;

95 }

96 } else { /* add two deltas from table */

97 int t;

98 if (c <= 0)

99 return AVERROR_INVALIDDATA;

100 t = dst[out - pitch] + (table[c * 2] - 128);

101 t = av_clip_uint8(t);

102 dst[out] = t;

103 out++;

104 t = dst[out - pitch] + (table[(c * 2) + 1] - 128);

105 t = av_clip_uint8(t);

106 dst[out] = t;

107 out++;

108 }

109 }

110 dst += pitch;

111 }

112 return 0;

113 }

114

115 static int ir2_decode_plane_inter(Ir2Context *ctx, int width, int height, uint8_t *dst,

116 int pitch, const uint8_t *table)

117 {

118 int j;

119 int out = 0;

120 int c;

121 int t;

122

123 if (width & 1)

124 return AVERROR_INVALIDDATA;

125

126 for (j = 0; j < height; j++) {

127 out = 0;

128 while (out < width) {

129 if (get_bits_left(&ctx->gb) <= 0)

130 return AVERROR_INVALIDDATA;

131 c = ir2_get_code(&ctx->gb);

132 if (c >= 0x80) { /* we have a skip */

133 c -= 0x7F;

134 out += c * 2;

135 } else { /* add two deltas from table */

136 if (c <= 0)

137 return AVERROR_INVALIDDATA;

138 t = dst[out] + (((table[c * 2] - 128)*3) >> 2);

139 t = av_clip_uint8(t);

140 dst[out] = t;

141 out++;

142 t = dst[out] + (((table[(c * 2) + 1] - 128)*3) >> 2);

143 t = av_clip_uint8(t);

144 dst[out] = t;

145 out++;

146 }

147 }

148 dst += pitch;

149 }

150 return 0;

151 }

152

153 static int ir2_decode_frame(AVCodecContext *avctx,

154 void *data, int *got_frame,

155 AVPacket *avpkt)

156 {

157 Ir2Context * const s = avctx->priv_data;

158 const uint8_t *buf = avpkt->data;

159 int buf_size = avpkt->size;

160 AVFrame *picture = data;

161 AVFrame * const p = s->picture;

162 int start, ret;

163 int ltab, ctab;

164

165 if ((ret = ff_reget_buffer(avctx, p, 0)) < 0)

166 return ret;

167

168 start = 48; /* hardcoded for now */

169

170 if (start >= buf_size) {

171 av_log(s->avctx, AV_LOG_ERROR, "input buffer size too small (%d)\n", buf_size);

172 return AVERROR_INVALIDDATA;

173 }

174

175 s->decode_delta = buf[18];

176

177 /* decide whether frame uses deltas or not */

178

179 if ((ret = init_get_bits8(&s->gb, buf + start, buf_size - start)) < 0)

180 return ret;

181

182 ltab = buf[0x22] & 3;

183 ctab = buf[0x22] >> 2;

184

185 if (ctab > 3) {

186 av_log(avctx, AV_LOG_ERROR, "ctab %d is invalid\n", ctab);

187 return AVERROR_INVALIDDATA;

188 }

189

190 if (s->decode_delta) { /* intraframe */

191 if ((ret = ir2_decode_plane(s, avctx->width, avctx->height,

192 p->data[0], p->linesize[0],

193 ir2_delta_table[ltab])) < 0)

194 return ret;

195

196 /* swapped U and V */

197 if ((ret = ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,

198 p->data[2], p->linesize[2],

199 ir2_delta_table[ctab])) < 0)

200 return ret;

201 if ((ret = ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,

202 p->data[1], p->linesize[1],

203 ir2_delta_table[ctab])) < 0)

204 return ret;

205 } else { /* interframe */

206 if ((ret = ir2_decode_plane_inter(s, avctx->width, avctx->height,

207 p->data[0], p->linesize[0],

208 ir2_delta_table[ltab])) < 0)

209 return ret;

210 /* swapped U and V */

211 if ((ret = ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,

212 p->data[2], p->linesize[2],

213 ir2_delta_table[ctab])) < 0)

214 return ret;

215 if ((ret = ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,

216 p->data[1], p->linesize[1],

217 ir2_delta_table[ctab])) < 0)

218 return ret;

219 }

220

221 if ((ret = av_frame_ref(picture, p)) < 0)

222 return ret;

223

224 *got_frame = 1;

225

226 return buf_size;

227 }

228

229 static av_cold void ir2_init_static(void)

230 {

231 INIT_VLC_STATIC_FROM_LENGTHS(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,

232 &ir2_tab[0][1], 2, &ir2_tab[0][0], 2, 1,

233 0, INIT_VLC_OUTPUT_LE, 1 << CODE_VLC_BITS);

234 }

235

236 static av_cold int ir2_decode_init(AVCodecContext *avctx)

237 {

238 static AVOnce init_static_once = AV_ONCE_INIT;

239 Ir2Context * const ic = avctx->priv_data;

240

241 ic->avctx = avctx;

242

243 avctx->pix_fmt= AV_PIX_FMT_YUV410P;

244

245 ic->picture = av_frame_alloc();

246 if (!ic->picture)

247 return AVERROR(ENOMEM);

248

249 ff_thread_once(&init_static_once, ir2_init_static);

250

251 return 0;

252 }

253

254 static av_cold int ir2_decode_end(AVCodecContext *avctx)

255 {

256 Ir2Context * const ic = avctx->priv_data;

257

258 av_frame_free(&ic->picture);

259

260 return 0;

261 }

262

263 const AVCodec ff_indeo2_decoder = {

264 .name = "indeo2",

265 .long_name = NULL_IF_CONFIG_SMALL("Intel Indeo 2"),

266 .type = AVMEDIA_TYPE_VIDEO,

267 .id = AV_CODEC_ID_INDEO2,

268 .priv_data_size = sizeof(Ir2Context),

269 .init = ir2_decode_init,

270 .close = ir2_decode_end,

271 .decode = ir2_decode_frame,

272 .capabilities = AV_CODEC_CAP_DR1,

273 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,

274 };

AVCodec

AVCodec.

Definition: codec.h:202

FF_CODEC_CAP_INIT_THREADSAFE

#define FF_CODEC_CAP_INIT_THREADSAFE

The codec does not modify any global variables in the init function, allowing to call the init functi...

Definition: internal.h:42

IR2_CODES

#define IR2_CODES

Definition: indeo2data.h:27

ff_indeo2_decoder

const AVCodec ff_indeo2_decoder

Definition: indeo2.c:263

get_bits_left

static int get_bits_left(GetBitContext *gb)

Definition: get_bits.h:850

AVERROR

Filter the word "frame" indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions

ir2_decode_plane_inter

static int ir2_decode_plane_inter(Ir2Context *ctx, int width, int height, uint8_t *dst, int pitch, const uint8_t *table)

Definition: indeo2.c:115

out

FILE * out

Definition: movenc.c:54

INIT_VLC_OUTPUT_LE

#define INIT_VLC_OUTPUT_LE

Definition: vlc.h:93

thread.h

indeo2data.h

av_frame_free

void av_frame_free(AVFrame **frame)

Free the frame and any dynamically allocated objects in it, e.g.

Definition: frame.c:109

ir2_vlc

static VLC ir2_vlc

Definition: indeo2.c:45

AVFrame

This structure describes decoded (raw) audio or video data.

Definition: frame.h:317

ir2_delta_table

static const uint8_t ir2_delta_table[4][256]

Definition: indeo2data.h:60

internal.h

AVPacket::data

uint8_t * data

Definition: packet.h:373

table

static const uint16_t table[]

Definition: prosumer.c:206

data

const char data[16]

Definition: mxf.c:143

Ir2Context::gb

GetBitContext gb

Definition: indeo2.c:40

get_vlc2

static av_always_inline int get_vlc2(GetBitContext *s, VLC_TYPE(*table)[2], int bits, int max_depth)

Parse a vlc code.

Definition: get_bits.h:798

AVFrame::data

uint8_t * data[AV_NUM_DATA_POINTERS]

pointer to the picture/channel planes.

Definition: frame.h:338

init

static int init

Definition: av_tx.c:47

ir2_decode_end

static av_cold int ir2_decode_end(AVCodecContext *avctx)

Definition: indeo2.c:254

GetBitContext

Definition: get_bits.h:62

av_frame_alloc

AVFrame * av_frame_alloc(void)

Allocate an AVFrame and set its fields to default values.

Definition: frame.c:97

ir2_tab

static const uint8_t ir2_tab[IR2_CODES][2]

Definition: indeo2data.h:28

ff_thread_once

static int ff_thread_once(char *control, void(*routine)(void))

Definition: thread.h:175

AV_LOG_ERROR

#define AV_LOG_ERROR

Something went wrong and cannot losslessly be recovered.

Definition: log.h:180

av_cold

#define av_cold

Definition: attributes.h:90

init_get_bits8

static int init_get_bits8(GetBitContext *s, const uint8_t *buffer, int byte_size)

Initialize GetBitContext.

Definition: get_bits.h:678

decode

static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)

Definition: decode_audio.c:71

width

#define width

#define s(width, name)

Definition: cbs_vp9.c:257

ctx

AVFormatContext * ctx

Definition: movenc.c:48

get_bits.h

ir2_get_code

static int ir2_get_code(GetBitContext *gb)

Definition: indeo2.c:48

AV_ONCE_INIT

#define AV_ONCE_INIT

Definition: thread.h:173

INIT_VLC_STATIC_FROM_LENGTHS

#define INIT_VLC_STATIC_FROM_LENGTHS(vlc, bits, nb_codes, lens, len_wrap, symbols, symbols_wrap, symbols_size, offset, flags, static_size)

Definition: vlc.h:126

mathops.h

ir2_init_static

static av_cold void ir2_init_static(void)

Definition: indeo2.c:229

AVOnce

#define AVOnce

Definition: thread.h:172

Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c

Definition: undefined.txt:32

AV_CODEC_ID_INDEO2

@ AV_CODEC_ID_INDEO2

Definition: codec_id.h:125

AV_CODEC_CAP_DR1

#define AV_CODEC_CAP_DR1

Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.

Definition: codec.h:52

AVPacket::size

int size

Definition: packet.h:374

NULL_IF_CONFIG_SMALL