/* * Chronomaster DFA Video Decoder * Copyright (c) 2011 Konstantin Shishkov * based on work by Vladimir "VAG" Gneushev * * This file is part of Libav. * * Libav is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * Libav is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include <inttypes.h> #include "avcodec.h" #include "bytestream.h" #include "internal.h" #include "libavutil/imgutils.h" #include "libavutil/mem.h" typedef struct DfaContext { uint32_t pal[256]; uint8_t *frame_buf; } DfaContext; static av_cold int dfa_decode_init(AVCodecContext *avctx) { DfaContext *s = avctx->priv_data; int ret; avctx->pix_fmt = AV_PIX_FMT_PAL8; if ((ret = av_image_check_size(avctx->width, avctx->height, 0, avctx)) < 0) return ret; s->frame_buf = av_mallocz(avctx->width * avctx->height); if (!s->frame_buf) return AVERROR(ENOMEM); return 0; } static int decode_copy(GetByteContext *gb, uint8_t *frame, int width, int height) { const int size = width * height; if (bytestream2_get_buffer(gb, frame, size) != size) return AVERROR_INVALIDDATA; return 0; } static int decode_tsw1(GetByteContext *gb, uint8_t *frame, int width, int height) { const uint8_t *frame_start = frame; const uint8_t *frame_end = frame + width * height; int mask = 0x10000, bitbuf = 0; int v, count, segments; unsigned offset; segments = bytestream2_get_le32(gb); offset = bytestream2_get_le32(gb); if (frame_end - frame <= offset) return AVERROR_INVALIDDATA; frame += offset; while (segments--) { if (bytestream2_get_bytes_left(gb) < 2) return AVERROR_INVALIDDATA; if (mask == 0x10000) { bitbuf = bytestream2_get_le16u(gb); mask = 1; } if (frame_end - frame < 2) return AVERROR_INVALIDDATA; if (bitbuf & mask) { v = bytestream2_get_le16(gb); offset = (v & 0x1FFF) << 1; count = ((v >> 13) + 2) << 1; if (frame - frame_start < offset || frame_end - frame < count) return AVERROR_INVALIDDATA; av_memcpy_backptr(frame, offset, count); frame += count; } else { *frame++ = bytestream2_get_byte(gb); *frame++ = bytestream2_get_byte(gb); } mask <<= 1; } return 0; } static int decode_dsw1(GetByteContext *gb, uint8_t *frame, int width, int height) { const uint8_t *frame_start = frame; const uint8_t *frame_end = frame + width * height; int mask = 0x10000, bitbuf = 0; int v, offset, count, segments; segments = bytestream2_get_le16(gb); while (segments--) { if (bytestream2_get_bytes_left(gb) < 2) return AVERROR_INVALIDDATA; if (mask == 0x10000) { bitbuf = bytestream2_get_le16u(gb); mask = 1; } if (frame_end - frame < 2) return AVERROR_INVALIDDATA; if (bitbuf & mask) { v = bytestream2_get_le16(gb); offset = (v & 0x1FFF) << 1; count = ((v >> 13) + 2) << 1; if (frame - frame_start < offset || frame_end - frame < count) return AVERROR_INVALIDDATA; av_memcpy_backptr(frame, offset, count); frame += count; } else if (bitbuf & (mask << 1)) { frame += bytestream2_get_le16(gb); } else { *frame++ = bytestream2_get_byte(gb); *frame++ = bytestream2_get_byte(gb); } mask <<= 2; } return 0; } static int decode_dds1(GetByteContext *gb, uint8_t *frame, int width, int height) { const uint8_t *frame_start = frame; const uint8_t *frame_end = frame + width * height; int mask = 0x10000, bitbuf = 0; int i, v, offset, count, segments; segments = bytestream2_get_le16(gb); while (segments--) { if (bytestream2_get_bytes_left(gb) < 2) return AVERROR_INVALIDDATA; if (mask == 0x10000) { bitbuf = bytestream2_get_le16u(gb); mask = 1; } if (bitbuf & mask) { v = bytestream2_get_le16(gb); offset = (v & 0x1FFF) << 2; count = ((v >> 13) + 2) << 1; if (frame - frame_start < offset || frame_end - frame < count*2 + width) return AVERROR_INVALIDDATA; for (i = 0; i < count; i++) { frame[0] = frame[1] = frame[width] = frame[width + 1] = frame[-offset]; frame += 2; } } else if (bitbuf & (mask << 1)) { v = bytestream2_get_le16(gb)*2; if (frame - frame_end < v) return AVERROR_INVALIDDATA; frame += v; } else { if (frame_end - frame < width + 3) return AVERROR_INVALIDDATA; frame[0] = frame[1] = frame[width] = frame[width + 1] = bytestream2_get_byte(gb); frame += 2; frame[0] = frame[1] = frame[width] = frame[width + 1] = bytestream2_get_byte(gb); frame += 2; } mask <<= 2; } return 0; } static int decode_bdlt(GetByteContext *gb, uint8_t *frame, int width, int height) { uint8_t *line_ptr; int count, lines, segments; count = bytestream2_get_le16(gb); if (count >= height) return AVERROR_INVALIDDATA; frame += width * count; lines = bytestream2_get_le16(gb); if (count + lines > height) return AVERROR_INVALIDDATA; while (lines--) { if (bytestream2_get_bytes_left(gb) < 1) return AVERROR_INVALIDDATA; line_ptr = frame; frame += width; segments = bytestream2_get_byteu(gb); while (segments--) { if (frame - line_ptr <= bytestream2_peek_byte(gb)) return AVERROR_INVALIDDATA; line_ptr += bytestream2_get_byte(gb); count = (int8_t)bytestream2_get_byte(gb); if (count >= 0) { if (frame - line_ptr < count) return AVERROR_INVALIDDATA; if (bytestream2_get_buffer(gb, line_ptr, count) != count) return AVERROR_INVALIDDATA; } else { count = -count; if (frame - line_ptr < count) return AVERROR_INVALIDDATA; memset(line_ptr, bytestream2_get_byte(gb), count); } line_ptr += count; } } return 0; } static int decode_wdlt(GetByteContext *gb, uint8_t *frame, int width, int height) { const uint8_t *frame_end = frame + width * height; uint8_t *line_ptr; int count, i, v, lines, segments; int y = 0; lines = bytestream2_get_le16(gb); if (lines > height) return AVERROR_INVALIDDATA; while (lines--) { if (bytestream2_get_bytes_left(gb) < 2) return AVERROR_INVALIDDATA; segments = bytestream2_get_le16u(gb); while ((segments & 0xC000) == 0xC000) { unsigned skip_lines = -(int16_t)segments; unsigned delta = -((int16_t)segments * width); if (frame_end - frame <= delta || y + lines + skip_lines > height) return AVERROR_INVALIDDATA; frame += delta; y += skip_lines; segments = bytestream2_get_le16(gb); } if (segments & 0x8000) { frame[width - 1] = segments & 0xFF; segments = bytestream2_get_le16(gb); } line_ptr = frame; if (frame_end - frame < width) return AVERROR_INVALIDDATA; frame += width; y++; while (segments--) { if (frame - line_ptr <= bytestream2_peek_byte(gb)) return AVERROR_INVALIDDATA; line_ptr += bytestream2_get_byte(gb); count = (int8_t)bytestream2_get_byte(gb); if (count >= 0) { if (frame - line_ptr < count * 2) return AVERROR_INVALIDDATA; if (bytestream2_get_buffer(gb, line_ptr, count * 2) != count * 2) return AVERROR_INVALIDDATA; line_ptr += count * 2; } else { count = -count; if (frame - line_ptr < count * 2) return AVERROR_INVALIDDATA; v = bytestream2_get_le16(gb); for (i = 0; i < count; i++) bytestream_put_le16(&line_ptr, v); } } } return 0; } static int decode_tdlt(GetByteContext *gb, uint8_t *frame, int width, int height) { const uint8_t *frame_end = frame + width * height; int segments = bytestream2_get_le32(gb); int skip, copy; while (segments--) { if (bytestream2_get_bytes_left(gb) < 2) return AVERROR_INVALIDDATA; copy = bytestream2_get_byteu(gb) * 2; skip = bytestream2_get_byteu(gb) * 2; if (frame_end - frame < copy + skip || bytestream2_get_bytes_left(gb) < copy) return AVERROR_INVALIDDATA; frame += skip; bytestream2_get_buffer(gb, frame, copy); frame += copy; } return 0; } static int decode_blck(GetByteContext *gb, uint8_t *frame, int width, int height) { memset(frame, 0, width * height); return 0; } typedef int (*chunk_decoder)(GetByteContext *gb, uint8_t *frame, int width, int height); static const chunk_decoder decoder[8] = { decode_copy, decode_tsw1, decode_bdlt, decode_wdlt, decode_tdlt, decode_dsw1, decode_blck, decode_dds1, }; static const char* chunk_name[8] = { "COPY", "TSW1", "BDLT", "WDLT", "TDLT", "DSW1", "BLCK", "DDS1" }; static int dfa_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt) { AVFrame *frame = data; DfaContext *s = avctx->priv_data; GetByteContext gb; const uint8_t *buf = avpkt->data; uint32_t chunk_type, chunk_size; uint8_t *dst; int ret; int i, pal_elems; if ((ret = ff_get_buffer(avctx, frame, 0))) { av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); return ret; } bytestream2_init(&gb, avpkt->data, avpkt->size); while (bytestream2_get_bytes_left(&gb) > 0) { bytestream2_skip(&gb, 4); chunk_size = bytestream2_get_le32(&gb); chunk_type = bytestream2_get_le32(&gb); if (!chunk_type) break; if (chunk_type == 1) { pal_elems = FFMIN(chunk_size / 3, 256); for (i = 0; i < pal_elems; i++) { s->pal[i] = bytestream2_get_be24(&gb) << 2; s->pal[i] |= (s->pal[i] >> 6) & 0x333; } frame->palette_has_changed = 1; } else if (chunk_type <= 9) { if (decoder[chunk_type - 2](&gb, s->frame_buf, avctx->width, avctx->height)) { av_log(avctx, AV_LOG_ERROR, "Error decoding %s chunk\n", chunk_name[chunk_type - 2]); return AVERROR_INVALIDDATA; } } else { av_log(avctx, AV_LOG_WARNING, "Ignoring unknown chunk type %"PRIu32"\n", chunk_type); } buf += chunk_size; } buf = s->frame_buf; dst = frame->data[0]; for (i = 0; i < avctx->height; i++) { memcpy(dst, buf, avctx->width); dst += frame->linesize[0]; buf += avctx->width; } memcpy(frame->data[1], s->pal, sizeof(s->pal)); *got_frame = 1; return avpkt->size; } static av_cold int dfa_decode_end(AVCodecContext *avctx) { DfaContext *s = avctx->priv_data; av_freep(&s->frame_buf); return 0; } AVCodec ff_dfa_decoder = { .name = "dfa", .long_name = NULL_IF_CONFIG_SMALL("Chronomaster DFA"), .type = AVMEDIA_TYPE_VIDEO, .id = AV_CODEC_ID_DFA, .priv_data_size = sizeof(DfaContext), .init = dfa_decode_init, .close = dfa_decode_end, .decode = dfa_decode_frame, .capabilities = AV_CODEC_CAP_DR1, };