FFmpeg: libavformat/smush.c Source File

FFmpeg

[フレーム]

libavformat

smush.c

Go to the documentation of this file.

1 /*

2 * LucasArts Smush demuxer

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 #include "libavutil/intreadwrite.h"

23 #include "avformat.h"

24 #include "internal.h"

25 #include "avio.h"

27 typedef struct {

28 int version;

29 int audio_stream_index;

30 int video_stream_index;

31 } SMUSHContext;

33 static int smush_read_probe(AVProbeData *p)

34 {

35 if (((AV_RL32(p->buf) == MKTAG('S', 'A', 'N', 'M') &&

36 AV_RL32(p->buf + 8) == MKTAG('S', 'H', 'D', 'R')) ||

37 (AV_RL32(p->buf) == MKTAG('A', 'N', 'I', 'M') &&

38 AV_RL32(p->buf + 8) == MKTAG('A', 'H', 'D', 'R')))) {

39 return AVPROBE_SCORE_MAX;

40 }

42 return 0;

43 }

45 static int smush_read_header(AVFormatContext *ctx)

46 {

47 SMUSHContext *smush = ctx->priv_data;

48 AVIOContext *pb = ctx->pb;

49 AVStream *vst, *ast;

50 uint32_t magic, nframes, size, subversion, i;

51 uint32_t width = 0, height = 0, got_audio = 0, read = 0;

52 uint32_t sample_rate, channels, palette[256];

54 magic = avio_rb32(pb);

55 avio_skip(pb, 4); // skip movie size

57 if (magic == MKBETAG('A', 'N', 'I', 'M')) {

58 if (avio_rb32(pb) != MKBETAG('A', 'H', 'D', 'R'))

59 return AVERROR_INVALIDDATA;

61 size = avio_rb32(pb);

62 if (size < 3 * 256 + 6)

63 return AVERROR_INVALIDDATA;

65 smush->version = 0;

66 subversion = avio_rl16(pb);

67 nframes = avio_rl16(pb);

69 avio_skip(pb, 2); // skip pad

71 for (i = 0; i < 256; i++)

72 palette[i] = avio_rb24(pb);

74 avio_skip(pb, size - (3 * 256 + 6));

75 } else if (magic == MKBETAG('S', 'A', 'N', 'M') ) {

76 if (avio_rb32(pb) != MKBETAG('S', 'H', 'D', 'R'))

77 return AVERROR_INVALIDDATA;

79 size = avio_rb32(pb);

80 if (size < 14)

81 return AVERROR_INVALIDDATA;

83 smush->version = 1;

84 subversion = avio_rl16(pb);

85 nframes = avio_rl32(pb);

86 avio_skip(pb, 2); // skip pad

87 width = avio_rl16(pb);

88 height = avio_rl16(pb);

89 avio_skip(pb, 2); // skip pad

90 avio_skip(pb, size - 14);

92 if (avio_rb32(pb) != MKBETAG('F', 'L', 'H', 'D'))

93 return AVERROR_INVALIDDATA;

95 size = avio_rb32(pb);

96 while (!got_audio && ((read + 8) < size)) {

97 uint32_t sig, chunk_size;

99 if (url_feof(pb))

100 return AVERROR_EOF;

101

102 sig = avio_rb32(pb);

103 chunk_size = avio_rb32(pb);

104 read += 8;

105 switch (sig) {

106 case MKBETAG('W', 'a', 'v', 'e'):

107 got_audio = 1;

108 sample_rate = avio_rl32(pb);

109 channels = avio_rl32(pb);

110 avio_skip(pb, chunk_size - 8);

111 read += chunk_size;

112 break;

113 case MKBETAG('B', 'l', '1', '6'):

114 case MKBETAG('A', 'N', 'N', 'O'):

115 avio_skip(pb, chunk_size);

116 read += chunk_size;

117 break;

118 default:

119 return AVERROR_INVALIDDATA;

120 break;

121 }

122 }

123

124 avio_skip(pb, size - read);

125 } else {

126 av_log(ctx, AV_LOG_ERROR, "Wrong magic\n");

127 return AVERROR_INVALIDDATA;

128 }

129

130 vst = avformat_new_stream(ctx, 0);

131 if (!vst)

132 return AVERROR(ENOMEM);

133

134 smush->video_stream_index = vst->index;

135

136 vst->start_time = 0;

137 vst->duration =

138 vst->nb_frames = nframes;

139 vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;

140 vst->codec->codec_id = AV_CODEC_ID_SANM;

141 vst->codec->codec_tag = 0;

142 vst->codec->width = width;

143 vst->codec->height = height;

144

145 avpriv_set_pts_info(vst, 64, 66667, 1000000);

146

147 if (!smush->version) {

148 if (ff_alloc_extradata(vst->codec, 1024 + 2))

149 return AVERROR(ENOMEM);

150

151 AV_WL16(vst->codec->extradata, subversion);

152 for (i = 0; i < 256; i++)

153 AV_WL32(vst->codec->extradata + 2 + i * 4, palette[i]);

154 }

155

156 if (got_audio) {

157 ast = avformat_new_stream(ctx, 0);

158 if (!ast)

159 return AVERROR(ENOMEM);

160

161 smush->audio_stream_index = ast->index;

162

163 ast->start_time = 0;

164 ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;

165 ast->codec->codec_id = AV_CODEC_ID_VIMA;

166 ast->codec->codec_tag = 0;

167 ast->codec->sample_rate = sample_rate;

168 ast->codec->channels = channels;

169

170 avpriv_set_pts_info(ast, 64, 1, ast->codec->sample_rate);

171 }

172

173 return 0;

174 }

175

176 static int smush_read_packet(AVFormatContext *ctx, AVPacket *pkt)

177 {

178 SMUSHContext *smush = ctx->priv_data;

179 AVIOContext *pb = ctx->pb;

180 int done = 0;

181

182 while (!done) {

183 uint32_t sig, size;

184

185 if (url_feof(pb))

186 return AVERROR_EOF;

187

188 sig = avio_rb32(pb);

189 size = avio_rb32(pb);

190

191 switch (sig) {

192 case MKBETAG('F', 'R', 'M', 'E'):

193 if (smush->version)

194 break;

195 if (av_get_packet(pb, pkt, size) < 0)

196 return AVERROR(EIO);

197

198 pkt->stream_index = smush->video_stream_index;

199 done = 1;

200 break;

201 case MKBETAG('B', 'l', '1', '6'):

202 if (av_get_packet(pb, pkt, size) < 0)

203 return AVERROR(EIO);

204

205 pkt->stream_index = smush->video_stream_index;

206 pkt->duration = 1;

207 done = 1;

208 break;

209 case MKBETAG('W', 'a', 'v', 'e'):

210 if (size < 13)

211 return AVERROR_INVALIDDATA;

212 if (av_get_packet(pb, pkt, size) < 13)

213 return AVERROR(EIO);

214

215 pkt->stream_index = smush->audio_stream_index;

216 pkt->flags |= AV_PKT_FLAG_KEY;

217 pkt->duration = AV_RB32(pkt->data);

218 if (pkt->duration == 0xFFFFFFFFu)

219 pkt->duration = AV_RB32(pkt->data + 8);

220 done = 1;

221 break;

222 default:

223 avio_skip(pb, size);

224 break;

225 }

226 }

227

228 return 0;

229 }

230

231 AVInputFormat ff_smush_demuxer = {

232 .name = "smush",

233 .long_name = NULL_IF_CONFIG_SMALL("LucasArts Smush"),

234 .priv_data_size = sizeof(SMUSHContext),

235 .read_probe = smush_read_probe,

236 .read_header = smush_read_header,

237 .read_packet = smush_read_packet,

238 };

Generated on Sat Jan 25 2014 19:52:05 for FFmpeg by doxygen 1.8.2