static int ulti_decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt) { const uint8_t *buf = avpkt->data; int buf_size = avpkt->size; UltimotionDecodeContext *s=avctx->priv_data; int modifier = 0; int uniq = 0; int mode = 0; int blocks = 0; int done = 0; int x = 0, y = 0; int i; int skip; int tmp; s->frame.reference = 1; s->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE; if (avctx->reget_buffer(avctx, &s->frame) < 0) { av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n"); return -1; } while(!done) { int idx; if(blocks >= s->blocks || y >= s->height) break;//all blocks decoded idx = *buf++; if((idx & 0xF8) == 0x70) { switch(idx) { case 0x70: //change modifier modifier = *buf++; if(modifier>1) av_log(avctx, AV_LOG_INFO, "warning: modifier must be 0 or 1, got %i\n", modifier); break; case 0x71: // set uniq flag uniq = 1; break; case 0x72: //toggle mode mode = !mode; break; case 0x73: //end-of-frame done = 1; break; case 0x74: //skip some blocks skip = *buf++; if ((blocks + skip) >= s->blocks) break; blocks += skip; x += skip * 8; while(x >= s->width) { x -= s->width; y += 8; } break; default: av_log(avctx, AV_LOG_INFO, "warning: unknown escape 0x%02X\n", idx); } } else { //handle one block int code; int cf; int angle = 0; uint8_t Y[4]; // luma samples of block int tx = 0, ty = 0; //coords of subblock int chroma = 0; if (mode || uniq) { uniq = 0; cf = 1; chroma = 0; } else { cf = 0; if (idx) chroma = *buf++; } for (i = 0; i < 4; i++) { // for every subblock code = (idx >> (6 - i*2)) & 3; //extract 2 bits if(!code) //skip subblock continue; if(cf) chroma = *buf++; tx = x + block_coords[i * 2]; ty = y + block_coords[(i * 2) + 1]; switch(code) { case 1: tmp = *buf++; angle = angle_by_index[(tmp >> 6) & 0x3]; Y[0] = tmp & 0x3F; Y[1] = Y[0]; if (angle) { Y[2] = Y[0]+1; if (Y[2] > 0x3F) Y[2] = 0x3F; Y[3] = Y[2]; } else { Y[2] = Y[0]; Y[3] = Y[0]; } break; case 2: if (modifier) { // unpack four luma samples tmp = bytestream_get_be24(&buf); Y[0] = (tmp >> 18) & 0x3F; Y[1] = (tmp >> 12) & 0x3F; Y[2] = (tmp >> 6) & 0x3F; Y[3] = tmp & 0x3F; angle = 16; } else { // retrieve luma samples from codebook tmp = bytestream_get_be16(&buf); angle = (tmp >> 12) & 0xF; tmp &= 0xFFF; tmp <<= 2; Y[0] = s->ulti_codebook[tmp]; Y[1] = s->ulti_codebook[tmp + 1]; Y[2] = s->ulti_codebook[tmp + 2]; Y[3] = s->ulti_codebook[tmp + 3]; } break; case 3: if (modifier) { // all 16 luma samples uint8_t Luma[16]; tmp = bytestream_get_be24(&buf); Luma[0] = (tmp >> 18) & 0x3F; Luma[1] = (tmp >> 12) & 0x3F; Luma[2] = (tmp >> 6) & 0x3F; Luma[3] = tmp & 0x3F; tmp = bytestream_get_be24(&buf); Luma[4] = (tmp >> 18) & 0x3F; Luma[5] = (tmp >> 12) & 0x3F; Luma[6] = (tmp >> 6) & 0x3F; Luma[7] = tmp & 0x3F; tmp = bytestream_get_be24(&buf); Luma[8] = (tmp >> 18) & 0x3F; Luma[9] = (tmp >> 12) & 0x3F; Luma[10] = (tmp >> 6) & 0x3F; Luma[11] = tmp & 0x3F; tmp = bytestream_get_be24(&buf); Luma[12] = (tmp >> 18) & 0x3F; Luma[13] = (tmp >> 12) & 0x3F; Luma[14] = (tmp >> 6) & 0x3F; Luma[15] = tmp & 0x3F; ulti_convert_yuv(&s->frame, tx, ty, Luma, chroma); } else { tmp = *buf++; if(tmp & 0x80) { angle = (tmp >> 4) & 0x7; tmp = (tmp << 8) + *buf++; Y[0] = (tmp >> 6) & 0x3F; Y[1] = tmp & 0x3F; Y[2] = (*buf++) & 0x3F; Y[3] = (*buf++) & 0x3F; ulti_grad(&s->frame, tx, ty, Y, chroma, angle); //draw block } else { // some patterns int f0, f1; f0 = *buf++; f1 = tmp; Y[0] = (*buf++) & 0x3F; Y[1] = (*buf++) & 0x3F; ulti_pattern(&s->frame, tx, ty, f1, f0, Y[0], Y[1], chroma); } } break; } if(code != 3) ulti_grad(&s->frame, tx, ty, Y, chroma, angle); // draw block } blocks++; x += 8; if(x >= s->width) { x = 0; y += 8; } } } *data_size=sizeof(AVFrame); *(AVFrame*)data= s->frame; return buf_size; }