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FFmpeg/libavcodec/dxtory.c
2013-08-30 15:47:38 +00:00

227 lines
6.6 KiB
C

/*
* Dxtory decoder
*
* Copyright (c) 2011 Konstantin Shishkov
*
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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 FFmpeg; 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;
}
static 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;
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);
}
slice_height = avctx->height / nslices;
if ((avctx->width & 1) || (slice_height & 1)) {
avpriv_request_sample(avctx, "slice dimensions %dx%d",
avctx->width, slice_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];
for (slice = 0; slice < nslices; slice++) {
slice_size = bytestream2_get_le32(&gb);
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;
}
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,
};