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00034 #include "libavutil/intreadwrite.h"
00035 #include "avcodec.h"
00036
00037 #define MM_PREAMBLE_SIZE 6
00038
00039 #define MM_TYPE_INTER 0x5
00040 #define MM_TYPE_INTRA 0x8
00041 #define MM_TYPE_INTRA_HH 0xc
00042 #define MM_TYPE_INTER_HH 0xd
00043 #define MM_TYPE_INTRA_HHV 0xe
00044 #define MM_TYPE_INTER_HHV 0xf
00045 #define MM_TYPE_PALETTE 0x31
00046
00047 typedef struct MmContext {
00048 AVCodecContext *avctx;
00049 AVFrame frame;
00050 int palette[AVPALETTE_COUNT];
00051 } MmContext;
00052
00053 static av_cold int mm_decode_init(AVCodecContext *avctx)
00054 {
00055 MmContext *s = avctx->priv_data;
00056
00057 s->avctx = avctx;
00058
00059 avctx->pix_fmt = PIX_FMT_PAL8;
00060
00061 s->frame.reference = 1;
00062
00063 return 0;
00064 }
00065
00066 static void mm_decode_pal(MmContext *s, const uint8_t *buf, const uint8_t *buf_end)
00067 {
00068 int i;
00069 buf += 4;
00070 for (i=0; i<128 && buf+2<buf_end; i++) {
00071 s->palette[i] = AV_RB24(buf);
00072 s->palette[i+128] = s->palette[i]<<2;
00073 buf += 3;
00074 }
00075 }
00076
00081 static void mm_decode_intra(MmContext * s, int half_horiz, int half_vert, const uint8_t *buf, int buf_size)
00082 {
00083 int i, x, y;
00084 i=0; x=0; y=0;
00085
00086 while(i<buf_size) {
00087 int run_length, color;
00088
00089 if (y >= s->avctx->height)
00090 return;
00091
00092 if (buf[i] & 0x80) {
00093 run_length = 1;
00094 color = buf[i];
00095 i++;
00096 }else{
00097 run_length = (buf[i] & 0x7f) + 2;
00098 color = buf[i+1];
00099 i+=2;
00100 }
00101
00102 if (half_horiz)
00103 run_length *=2;
00104
00105 if (color) {
00106 memset(s->frame.data[0] + y*s->frame.linesize[0] + x, color, run_length);
00107 if (half_vert)
00108 memset(s->frame.data[0] + (y+1)*s->frame.linesize[0] + x, color, run_length);
00109 }
00110 x+= run_length;
00111
00112 if (x >= s->avctx->width) {
00113 x=0;
00114 y += 1 + half_vert;
00115 }
00116 }
00117 }
00118
00119
00120
00121
00122
00123 static void mm_decode_inter(MmContext * s, int half_horiz, int half_vert, const uint8_t *buf, int buf_size)
00124 {
00125 const int data_ptr = 2 + AV_RL16(&buf[0]);
00126 int d, r, y;
00127 d = data_ptr; r = 2; y = 0;
00128
00129 while(r < data_ptr) {
00130 int i, j;
00131 int length = buf[r] & 0x7f;
00132 int x = buf[r+1] + ((buf[r] & 0x80) << 1);
00133 r += 2;
00134
00135 if (length==0) {
00136 y += x;
00137 continue;
00138 }
00139
00140 if (y + half_vert >= s->avctx->height)
00141 return;
00142
00143 for(i=0; i<length; i++) {
00144 for(j=0; j<8; j++) {
00145 int replace = (buf[r+i] >> (7-j)) & 1;
00146 if (replace) {
00147 int color = buf[d];
00148 s->frame.data[0][y*s->frame.linesize[0] + x] = color;
00149 if (half_horiz)
00150 s->frame.data[0][y*s->frame.linesize[0] + x + 1] = color;
00151 if (half_vert) {
00152 s->frame.data[0][(y+1)*s->frame.linesize[0] + x] = color;
00153 if (half_horiz)
00154 s->frame.data[0][(y+1)*s->frame.linesize[0] + x + 1] = color;
00155 }
00156 d++;
00157 }
00158 x += 1 + half_horiz;
00159 }
00160 }
00161
00162 r += length;
00163 y += 1 + half_vert;
00164 }
00165 }
00166
00167 static int mm_decode_frame(AVCodecContext *avctx,
00168 void *data, int *data_size,
00169 AVPacket *avpkt)
00170 {
00171 const uint8_t *buf = avpkt->data;
00172 int buf_size = avpkt->size;
00173 MmContext *s = avctx->priv_data;
00174 const uint8_t *buf_end = buf+buf_size;
00175 int type;
00176
00177 type = AV_RL16(&buf[0]);
00178 buf += MM_PREAMBLE_SIZE;
00179 buf_size -= MM_PREAMBLE_SIZE;
00180
00181 if (avctx->reget_buffer(avctx, &s->frame) < 0) {
00182 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
00183 return -1;
00184 }
00185
00186 switch(type) {
00187 case MM_TYPE_PALETTE : mm_decode_pal(s, buf, buf_end); return buf_size;
00188 case MM_TYPE_INTRA : mm_decode_intra(s, 0, 0, buf, buf_size); break;
00189 case MM_TYPE_INTRA_HH : mm_decode_intra(s, 1, 0, buf, buf_size); break;
00190 case MM_TYPE_INTRA_HHV : mm_decode_intra(s, 1, 1, buf, buf_size); break;
00191 case MM_TYPE_INTER : mm_decode_inter(s, 0, 0, buf, buf_size); break;
00192 case MM_TYPE_INTER_HH : mm_decode_inter(s, 1, 0, buf, buf_size); break;
00193 case MM_TYPE_INTER_HHV : mm_decode_inter(s, 1, 1, buf, buf_size); break;
00194 default :
00195 return -1;
00196 }
00197
00198 memcpy(s->frame.data[1], s->palette, AVPALETTE_SIZE);
00199
00200 *data_size = sizeof(AVFrame);
00201 *(AVFrame*)data = s->frame;
00202
00203 return buf_size;
00204 }
00205
00206 static av_cold int mm_decode_end(AVCodecContext *avctx)
00207 {
00208 MmContext *s = avctx->priv_data;
00209
00210 if(s->frame.data[0])
00211 avctx->release_buffer(avctx, &s->frame);
00212
00213 return 0;
00214 }
00215
00216 AVCodec ff_mmvideo_decoder = {
00217 .name = "mmvideo",
00218 .type = AVMEDIA_TYPE_VIDEO,
00219 .id = CODEC_ID_MMVIDEO,
00220 .priv_data_size = sizeof(MmContext),
00221 .init = mm_decode_init,
00222 .close = mm_decode_end,
00223 .decode = mm_decode_frame,
00224 .capabilities = CODEC_CAP_DR1,
00225 .long_name = NULL_IF_CONFIG_SMALL("American Laser Games MM Video"),
00226 };