static int bethsoftvid_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt) { BethsoftvidContext * vid = avctx->priv_data; char block_type; uint8_t * dst; uint8_t * frame_end; int remaining = avctx->width; // number of bytes remaining on a line int wrap_to_next_line; int code, ret; int yoffset; if ((ret = ff_reget_buffer(avctx, vid->frame)) < 0) return ret; wrap_to_next_line = vid->frame->linesize[0] - avctx->width; if (avpkt->side_data_elems > 0 && avpkt->side_data[0].type == AV_PKT_DATA_PALETTE) { bytestream2_init(&vid->g, avpkt->side_data[0].data, avpkt->side_data[0].size); if ((ret = set_palette(vid)) < 0) return ret; } bytestream2_init(&vid->g, avpkt->data, avpkt->size); dst = vid->frame->data[0]; frame_end = vid->frame->data[0] + vid->frame->linesize[0] * avctx->height; switch(block_type = bytestream2_get_byte(&vid->g)){ case PALETTE_BLOCK: { *got_frame = 0; if ((ret = set_palette(vid)) < 0) { av_log(avctx, AV_LOG_ERROR, "error reading palette\n"); return ret; } return bytestream2_tell(&vid->g); } case VIDEO_YOFF_P_FRAME: yoffset = bytestream2_get_le16(&vid->g); if(yoffset >= avctx->height) return AVERROR_INVALIDDATA; dst += vid->frame->linesize[0] * yoffset; } // main code while((code = bytestream2_get_byte(&vid->g))){ int length = code & 0x7f; // copy any bytes starting at the current position, and ending at the frame width while(length > remaining){ if(code < 0x80) bytestream2_get_buffer(&vid->g, dst, remaining); else if(block_type == VIDEO_I_FRAME) memset(dst, bytestream2_peek_byte(&vid->g), remaining); length -= remaining; // decrement the number of bytes to be copied dst += remaining + wrap_to_next_line; // skip over extra bytes at end of frame remaining = avctx->width; if(dst == frame_end) goto end; } // copy any remaining bytes after / if line overflows if(code < 0x80) bytestream2_get_buffer(&vid->g, dst, length); else if(block_type == VIDEO_I_FRAME) memset(dst, bytestream2_get_byte(&vid->g), length); remaining -= length; dst += length; } end: if ((ret = av_frame_ref(data, vid->frame)) < 0) return ret; *got_frame = 1; return avpkt->size; }
static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt) { PicContext *s = avctx->priv_data; uint32_t *palette; int bits_per_plane, bpp, etype, esize, npal, pos_after_pal; int i, x, y, plane, tmp; bytestream2_init(&s->g, avpkt->data, avpkt->size); if (bytestream2_get_bytes_left(&s->g) < 11) return AVERROR_INVALIDDATA; if (bytestream2_get_le16u(&s->g) != 0x1234) return AVERROR_INVALIDDATA; s->width = bytestream2_get_le16u(&s->g); s->height = bytestream2_get_le16u(&s->g); bytestream2_skip(&s->g, 4); tmp = bytestream2_get_byteu(&s->g); bits_per_plane = tmp & 0xF; s->nb_planes = (tmp >> 4) + 1; bpp = bits_per_plane * s->nb_planes; if (bits_per_plane > 8 || bpp < 1 || bpp > 32) { av_log_ask_for_sample(s, "unsupported bit depth\n"); return AVERROR_INVALIDDATA; } if (bytestream2_peek_byte(&s->g) == 0xFF) { bytestream2_skip(&s->g, 2); etype = bytestream2_get_le16(&s->g); esize = bytestream2_get_le16(&s->g); if (bytestream2_get_bytes_left(&s->g) < esize) return AVERROR_INVALIDDATA; } else { etype = -1; esize = 0; } avctx->pix_fmt = PIX_FMT_PAL8; if (s->width != avctx->width && s->height != avctx->height) { if (av_image_check_size(s->width, s->height, 0, avctx) < 0) return -1; avcodec_set_dimensions(avctx, s->width, s->height); if (s->frame.data[0]) avctx->release_buffer(avctx, &s->frame); } if (avctx->get_buffer(avctx, &s->frame) < 0){ av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); return -1; } memset(s->frame.data[0], 0, s->height * s->frame.linesize[0]); s->frame.pict_type = AV_PICTURE_TYPE_I; s->frame.palette_has_changed = 1; pos_after_pal = bytestream2_tell(&s->g) + esize; palette = (uint32_t*)s->frame.data[1]; if (etype == 1 && esize > 1 && bytestream2_peek_byte(&s->g) < 6) { int idx = bytestream2_get_byte(&s->g); npal = 4; for (i = 0; i < npal; i++) palette[i] = ff_cga_palette[ cga_mode45_index[idx][i] ]; } else if (etype == 2) { npal = FFMIN(esize, 16); for (i = 0; i < npal; i++) { int pal_idx = bytestream2_get_byte(&s->g); palette[i] = ff_cga_palette[FFMIN(pal_idx, 16)]; } } else if (etype == 3) { npal = FFMIN(esize, 16); for (i = 0; i < npal; i++) { int pal_idx = bytestream2_get_byte(&s->g); palette[i] = ff_ega_palette[FFMIN(pal_idx, 63)]; } } else if (etype == 4 || etype == 5) { npal = FFMIN(esize / 3, 256); for (i = 0; i < npal; i++) palette[i] = bytestream2_get_be24(&s->g) << 2; } else { if (bpp == 1) { npal = 2; palette[0] = 0x000000; palette[1] = 0xFFFFFF; } else if (bpp == 2) { npal = 4; for (i = 0; i < npal; i++) palette[i] = ff_cga_palette[ cga_mode45_index[0][i] ]; } else { npal = 16; memcpy(palette, ff_cga_palette, npal * 4); } } // fill remaining palette entries memset(palette + npal, 0, AVPALETTE_SIZE - npal * 4); // skip remaining palette bytes bytestream2_seek(&s->g, pos_after_pal, SEEK_SET); x = 0; y = s->height - 1; plane = 0; if (bytestream2_get_le16(&s->g)) { while (bytestream2_get_bytes_left(&s->g) >= 6) { int stop_size, marker, t1, t2; t1 = bytestream2_get_bytes_left(&s->g); t2 = bytestream2_get_le16(&s->g); stop_size = t1 - FFMIN(t1, t2); // ignore uncompressed block size bytestream2_skip(&s->g, 2); marker = bytestream2_get_byte(&s->g); while (plane < s->nb_planes && bytestream2_get_bytes_left(&s->g) > stop_size) { int run = 1; int val = bytestream2_get_byte(&s->g); if (val == marker) { run = bytestream2_get_byte(&s->g); if (run == 0) run = bytestream2_get_le16(&s->g); val = bytestream2_get_byte(&s->g); } if (!bytestream2_get_bytes_left(&s->g)) break; if (bits_per_plane == 8) { picmemset_8bpp(s, val, run, &x, &y); if (y < 0) break; } else { picmemset(s, val, run, &x, &y, &plane, bits_per_plane); } } } } else { av_log_ask_for_sample(s, "uncompressed image\n"); return avpkt->size; } *data_size = sizeof(AVFrame); *(AVFrame*)data = s->frame; return avpkt->size; }