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FFmpeg/libavcodec/dfa.c
Reimar Döffinger 0b378e8aa9 DFA: fix "skip frame" TSW1 encoding.
Previously the decoder would raise an error.
The end result is the same, the time stamps only change
because regression tests create time stamps incorrectly.

Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
2012-01-28 21:59:01 +01:00

399 lines
12 KiB
C

/*
* Chronomaster DFA Video Decoder
* Copyright (c) 2011 Konstantin Shishkov
* based on work by Vladimir "VAG" Gneushev
*
* 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
*/
#include "avcodec.h"
#include "libavutil/intreadwrite.h"
#include "bytestream.h"
#include "libavutil/lzo.h" // for av_memcpy_backptr
typedef struct DfaContext {
AVFrame pic;
uint32_t pal[256];
uint8_t *frame_buf;
} DfaContext;
static av_cold int dfa_decode_init(AVCodecContext *avctx)
{
DfaContext *s = avctx->priv_data;
avctx->pix_fmt = PIX_FMT_PAL8;
s->frame_buf = av_mallocz(avctx->width * avctx->height + AV_LZO_OUTPUT_PADDING);
if (!s->frame_buf)
return AVERROR(ENOMEM);
return 0;
}
static int decode_copy(uint8_t *frame, int width, int height,
const uint8_t *src, const uint8_t *src_end)
{
const int size = width * height;
if (src_end - src < size)
return -1;
bytestream_get_buffer(&src, frame, size);
return 0;
}
static int decode_tsw1(uint8_t *frame, int width, int height,
const uint8_t *src, const uint8_t *src_end)
{
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 = bytestream_get_le32(&src);
offset = bytestream_get_le32(&src);
if (segments == 0 && offset == frame_end - frame)
return 0; // skip frame
if (frame_end - frame <= offset)
return -1;
frame += offset;
while (segments--) {
if (mask == 0x10000) {
if (src >= src_end)
return -1;
bitbuf = bytestream_get_le16(&src);
mask = 1;
}
if (src_end - src < 2 || frame_end - frame < 2)
return -1;
if (bitbuf & mask) {
v = bytestream_get_le16(&src);
offset = (v & 0x1FFF) << 1;
count = ((v >> 13) + 2) << 1;
if (frame - frame_start < offset || frame_end - frame < count)
return -1;
av_memcpy_backptr(frame, offset, count);
frame += count;
} else {
*frame++ = *src++;
*frame++ = *src++;
}
mask <<= 1;
}
return 0;
}
static int decode_dsw1(uint8_t *frame, int width, int height,
const uint8_t *src, const uint8_t *src_end)
{
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 = bytestream_get_le16(&src);
while (segments--) {
if (mask == 0x10000) {
if (src >= src_end)
return -1;
bitbuf = bytestream_get_le16(&src);
mask = 1;
}
if (src_end - src < 2 || frame_end - frame < 2)
return -1;
if (bitbuf & mask) {
v = bytestream_get_le16(&src);
offset = (v & 0x1FFF) << 1;
count = ((v >> 13) + 2) << 1;
if (frame - frame_start < offset || frame_end - frame < count)
return -1;
// can't use av_memcpy_backptr() since it can overwrite following pixels
for (v = 0; v < count; v++)
frame[v] = frame[v - offset];
frame += count;
} else if (bitbuf & (mask << 1)) {
frame += bytestream_get_le16(&src);
} else {
*frame++ = *src++;
*frame++ = *src++;
}
mask <<= 2;
}
return 0;
}
static int decode_dds1(uint8_t *frame, int width, int height,
const uint8_t *src, const uint8_t *src_end)
{
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 = bytestream_get_le16(&src);
while (segments--) {
if (mask == 0x10000) {
if (src >= src_end)
return -1;
bitbuf = bytestream_get_le16(&src);
mask = 1;
}
if (src_end - src < 2 || frame_end - frame < 2)
return -1;
if (bitbuf & mask) {
v = bytestream_get_le16(&src);
offset = (v & 0x1FFF) << 2;
count = ((v >> 13) + 2) << 1;
if (frame - frame_start < offset || frame_end - frame < count*2 + width)
return -1;
for (i = 0; i < count; i++) {
frame[0] = frame[1] =
frame[width] = frame[width + 1] = frame[-offset];
frame += 2;
}
} else if (bitbuf & (mask << 1)) {
frame += bytestream_get_le16(&src) * 2;
} else {
frame[0] = frame[1] =
frame[width] = frame[width + 1] = *src++;
frame += 2;
frame[0] = frame[1] =
frame[width] = frame[width + 1] = *src++;
frame += 2;
}
mask <<= 2;
}
return 0;
}
static int decode_bdlt(uint8_t *frame, int width, int height,
const uint8_t *src, const uint8_t *src_end)
{
uint8_t *line_ptr;
int count, lines, segments;
count = bytestream_get_le16(&src);
if (count >= height)
return -1;
frame += width * count;
lines = bytestream_get_le16(&src);
if (count + lines > height || src >= src_end)
return -1;
while (lines--) {
line_ptr = frame;
frame += width;
segments = *src++;
while (segments--) {
if (src_end - src < 3)
return -1;
if (frame - line_ptr <= *src)
return -1;
line_ptr += *src++;
count = (int8_t)*src++;
if (count >= 0) {
if (frame - line_ptr < count || src_end - src < count)
return -1;
bytestream_get_buffer(&src, line_ptr, count);
} else {
count = -count;
if (frame - line_ptr < count || src >= src_end)
return -1;
memset(line_ptr, *src++, count);
}
line_ptr += count;
}
}
return 0;
}
static int decode_wdlt(uint8_t *frame, int width, int height,
const uint8_t *src, const uint8_t *src_end)
{
const uint8_t *frame_end = frame + width * height;
uint8_t *line_ptr;
int count, i, v, lines, segments;
lines = bytestream_get_le16(&src);
if (lines > height || src >= src_end)
return -1;
while (lines--) {
segments = bytestream_get_le16(&src);
while ((segments & 0xC000) == 0xC000) {
unsigned delta = -((int16_t)segments * width);
if (frame_end - frame <= delta)
return -1;
frame += delta;
segments = bytestream_get_le16(&src);
}
if (segments & 0x8000) {
frame[width - 1] = segments & 0xFF;
segments = bytestream_get_le16(&src);
}
line_ptr = frame;
frame += width;
while (segments--) {
if (src_end - src < 2)
return -1;
if (frame - line_ptr <= *src)
return -1;
line_ptr += *src++;
count = (int8_t)*src++;
if (count >= 0) {
if (frame - line_ptr < count*2 || src_end - src < count*2)
return -1;
bytestream_get_buffer(&src, line_ptr, count*2);
line_ptr += count * 2;
} else {
count = -count;
if (frame - line_ptr < count*2 || src_end - src < 2)
return -1;
v = bytestream_get_le16(&src);
for (i = 0; i < count; i++)
bytestream_put_le16(&line_ptr, v);
}
}
}
return 0;
}
static int decode_unk6(uint8_t *frame, int width, int height,
const uint8_t *src, const uint8_t *src_end)
{
return -1;
}
static int decode_blck(uint8_t *frame, int width, int height,
const uint8_t *src, const uint8_t *src_end)
{
memset(frame, 0, width * height);
return 0;
}
typedef int (*chunk_decoder)(uint8_t *frame, int width, int height,
const uint8_t *src, const uint8_t *src_end);
static const chunk_decoder decoder[8] = {
decode_copy, decode_tsw1, decode_bdlt, decode_wdlt,
decode_unk6, decode_dsw1, decode_blck, decode_dds1,
};
static const char* chunk_name[8] = {
"COPY", "TSW1", "BDLT", "WDLT", "????", "DSW1", "BLCK", "DDS1"
};
static int dfa_decode_frame(AVCodecContext *avctx,
void *data, int *data_size,
AVPacket *avpkt)
{
DfaContext *s = avctx->priv_data;
const uint8_t *buf = avpkt->data;
const uint8_t *buf_end = avpkt->data + avpkt->size;
const uint8_t *tmp_buf;
uint32_t chunk_type, chunk_size;
uint8_t *dst;
int ret;
int i, pal_elems;
if (s->pic.data[0])
avctx->release_buffer(avctx, &s->pic);
if ((ret = avctx->get_buffer(avctx, &s->pic))) {
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
return ret;
}
while (buf < buf_end) {
chunk_size = AV_RL32(buf + 4);
chunk_type = AV_RL32(buf + 8);
buf += 12;
if (buf_end - buf < chunk_size) {
av_log(avctx, AV_LOG_ERROR, "Chunk size is too big (%d bytes)\n", chunk_size);
return -1;
}
if (!chunk_type)
break;
if (chunk_type == 1) {
pal_elems = FFMIN(chunk_size / 3, 256);
tmp_buf = buf;
for (i = 0; i < pal_elems; i++) {
s->pal[i] = bytestream_get_be24(&tmp_buf) << 2;
s->pal[i] |= 0xFF << 24 | (s->pal[i] >> 6) & 0x30303;
}
s->pic.palette_has_changed = 1;
} else if (chunk_type <= 9) {
if (decoder[chunk_type - 2](s->frame_buf, avctx->width, avctx->height,
buf, buf + chunk_size)) {
av_log(avctx, AV_LOG_ERROR, "Error decoding %s chunk\n",
chunk_name[chunk_type - 2]);
return -1;
}
} else {
av_log(avctx, AV_LOG_WARNING, "Ignoring unknown chunk type %d\n",
chunk_type);
}
buf += chunk_size;
}
buf = s->frame_buf;
dst = s->pic.data[0];
for (i = 0; i < avctx->height; i++) {
memcpy(dst, buf, avctx->width);
dst += s->pic.linesize[0];
buf += avctx->width;
}
memcpy(s->pic.data[1], s->pal, sizeof(s->pal));
*data_size = sizeof(AVFrame);
*(AVFrame*)data = s->pic;
return avpkt->size;
}
static av_cold int dfa_decode_end(AVCodecContext *avctx)
{
DfaContext *s = avctx->priv_data;
if (s->pic.data[0])
avctx->release_buffer(avctx, &s->pic);
av_freep(&s->frame_buf);
return 0;
}
AVCodec ff_dfa_decoder = {
.name = "dfa",
.type = AVMEDIA_TYPE_VIDEO,
.id = CODEC_ID_DFA,
.priv_data_size = sizeof(DfaContext),
.init = dfa_decode_init,
.close = dfa_decode_end,
.decode = dfa_decode_frame,
.capabilities = CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("Chronomaster DFA"),
};