/* * Dxtory decoder * * Copyright (c) 2011 Konstantin Shishkov * * 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 */ #define BITSTREAM_READER_LE #include "avcodec.h" #include "bytestream.h" #include "get_bits.h" #include "internal.h" #include "unary.h" #include "libavutil/common.h" #include "libavutil/intreadwrite.h" static int dxtory_decode_v1(AVCodecContext *avctx, AVFrame *pic, const uint8_t *src, int src_size) { int h, w; uint8_t *Y1, *Y2, *U, *V; int ret; if (src_size < avctx->width * avctx->height * 3 / 2) { av_log(avctx, AV_LOG_ERROR, "packet too small\n"); return AVERROR_INVALIDDATA; } avctx->pix_fmt = AV_PIX_FMT_YUV420P; if ((ret = ff_get_buffer(avctx, pic, 0)) < 0) return ret; Y1 = pic->data[0]; Y2 = pic->data[0] + pic->linesize[0]; U = pic->data[1]; V = pic->data[2]; for (h = 0; h < avctx->height; h += 2) { for (w = 0; w < avctx->width; w += 2) { AV_COPY16(Y1 + w, src); AV_COPY16(Y2 + w, src + 2); U[w >> 1] = src[4] + 0x80; V[w >> 1] = src[5] + 0x80; src += 6; } Y1 += pic->linesize[0] << 1; Y2 += pic->linesize[0] << 1; U += pic->linesize[1]; V += pic->linesize[2]; } return 0; } const uint8_t def_lru[8] = { 0x00, 0x20, 0x40, 0x60, 0x80, 0xA0, 0xC0, 0xFF }; static inline uint8_t decode_sym(GetBitContext *gb, uint8_t lru[8]) { uint8_t c, val; c = get_unary(gb, 0, 8); if (!c) { val = get_bits(gb, 8); memmove(lru + 1, lru, sizeof(*lru) * (8 - 1)); } else { val = lru[c - 1]; memmove(lru + 1, lru, sizeof(*lru) * (c - 1)); } lru[0] = val; return val; } static int dx2_decode_slice(GetBitContext *gb, int width, int height, uint8_t *Y, uint8_t *U, uint8_t *V, int ystride, int ustride, int vstride) { int x, y, i; uint8_t lru[3][8]; for (i = 0; i < 3; i++) memcpy(lru[i], def_lru, 8 * sizeof(*def_lru)); for (y = 0; y < height; y+=2) { for (x = 0; x < width; x += 2) { Y[x + 0 + 0 * ystride] = decode_sym(gb, lru[0]); Y[x + 1 + 0 * ystride] = decode_sym(gb, lru[0]); Y[x + 0 + 1 * ystride] = decode_sym(gb, lru[0]); Y[x + 1 + 1 * ystride] = decode_sym(gb, lru[0]); U[x >> 1] = decode_sym(gb, lru[1]) ^ 0x80; V[x >> 1] = decode_sym(gb, lru[2]) ^ 0x80; } Y += ystride << 1; U += ustride; V += vstride; } return 0; } static int dxtory_decode_v2(AVCodecContext *avctx, AVFrame *pic, const uint8_t *src, int src_size) { GetByteContext gb; GetBitContext gb2; int nslices, slice, slice_height, ref_slice_height; int cur_y, next_y; uint32_t off, slice_size; uint8_t *Y, *U, *V; int ret; bytestream2_init(&gb, src, src_size); nslices = bytestream2_get_le16(&gb); off = FFALIGN(nslices * 4 + 2, 16); if (src_size < off) { av_log(avctx, AV_LOG_ERROR, "no slice data\n"); return AVERROR_INVALIDDATA; } if (!nslices || avctx->height % nslices) { avpriv_request_sample(avctx, "%d slices for %dx%d", nslices, avctx->width, avctx->height); return AVERROR(ENOSYS); } ref_slice_height = avctx->height / nslices; if ((avctx->width & 1) || (avctx->height & 1)) { avpriv_request_sample(avctx, "Frame dimensions %dx%d", avctx->width, avctx->height); } avctx->pix_fmt = AV_PIX_FMT_YUV420P; if ((ret = ff_get_buffer(avctx, pic, 0)) < 0) return ret; Y = pic->data[0]; U = pic->data[1]; V = pic->data[2]; cur_y = 0; next_y = ref_slice_height; for (slice = 0; slice < nslices; slice++) { slice_size = bytestream2_get_le32(&gb); slice_height = (next_y & ~1) - (cur_y & ~1); if (slice_size > src_size - off) { av_log(avctx, AV_LOG_ERROR, "invalid slice size %d (only %d bytes left)\n", slice_size, src_size - off); return AVERROR_INVALIDDATA; } if (slice_size <= 16) { av_log(avctx, AV_LOG_ERROR, "invalid slice size %d\n", slice_size); return AVERROR_INVALIDDATA; } if (AV_RL32(src + off) != slice_size - 16) { av_log(avctx, AV_LOG_ERROR, "Slice sizes mismatch: got %d instead of %d\n", AV_RL32(src + off), slice_size - 16); } init_get_bits(&gb2, src + off + 16, (slice_size - 16) * 8); dx2_decode_slice(&gb2, avctx->width, slice_height, Y, U, V, pic->linesize[0], pic->linesize[1], pic->linesize[2]); Y += pic->linesize[0] * slice_height; U += pic->linesize[1] * (slice_height >> 1); V += pic->linesize[2] * (slice_height >> 1); off += slice_size; cur_y = next_y; next_y += ref_slice_height; } return 0; } static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt) { AVFrame *pic = data; const uint8_t *src = avpkt->data; int ret; if (avpkt->size < 16) { av_log(avctx, AV_LOG_ERROR, "packet too small\n"); return AVERROR_INVALIDDATA; } switch (AV_RB32(src)) { case 0x02000001: ret = dxtory_decode_v1(avctx, pic, src + 16, avpkt->size - 16); break; case 0x02000009: ret = dxtory_decode_v2(avctx, pic, src + 16, avpkt->size - 16); break; default: avpriv_request_sample(avctx, "Frame header %X", AV_RB32(src)); return AVERROR_PATCHWELCOME; } if (ret) return ret; pic->pict_type = AV_PICTURE_TYPE_I; pic->key_frame = 1; *got_frame = 1; return avpkt->size; } AVCodec ff_dxtory_decoder = { .name = "dxtory", .long_name = NULL_IF_CONFIG_SMALL("Dxtory"), .type = AVMEDIA_TYPE_VIDEO, .id = AV_CODEC_ID_DXTORY, .decode = decode_frame, .capabilities = CODEC_CAP_DR1, };