mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-11-21 10:55:51 +02:00
def97856de
Express bitfields more simply. Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
272 lines
7.8 KiB
C
272 lines
7.8 KiB
C
/*
|
|
* Tiertex Limited SEQ Video Decoder
|
|
* Copyright (c) 2006 Gregory Montoir (cyx@users.sourceforge.net)
|
|
*
|
|
* 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
|
|
*/
|
|
|
|
/**
|
|
* @file
|
|
* Tiertex Limited SEQ video decoder
|
|
*/
|
|
|
|
#include "avcodec.h"
|
|
#define BITSTREAM_READER_LE
|
|
#include "get_bits.h"
|
|
#include "internal.h"
|
|
|
|
|
|
typedef struct SeqVideoContext {
|
|
AVCodecContext *avctx;
|
|
AVFrame *frame;
|
|
} SeqVideoContext;
|
|
|
|
|
|
static const unsigned char *seq_unpack_rle_block(const unsigned char *src,
|
|
const unsigned char *src_end,
|
|
unsigned char *dst, int dst_size)
|
|
{
|
|
int i, len, sz;
|
|
GetBitContext gb;
|
|
int code_table[64];
|
|
|
|
/* get the rle codes */
|
|
init_get_bits(&gb, src, (src_end - src) * 8);
|
|
for (i = 0, sz = 0; i < 64 && sz < dst_size; i++) {
|
|
if (get_bits_left(&gb) < 4)
|
|
return NULL;
|
|
code_table[i] = get_sbits(&gb, 4);
|
|
sz += FFABS(code_table[i]);
|
|
}
|
|
src += (get_bits_count(&gb) + 7) / 8;
|
|
|
|
/* do the rle unpacking */
|
|
for (i = 0; i < 64 && dst_size > 0; i++) {
|
|
len = code_table[i];
|
|
if (len < 0) {
|
|
len = -len;
|
|
if (src_end - src < 1)
|
|
return NULL;
|
|
memset(dst, *src++, FFMIN(len, dst_size));
|
|
} else {
|
|
if (src_end - src < len)
|
|
return NULL;
|
|
memcpy(dst, src, FFMIN(len, dst_size));
|
|
src += len;
|
|
}
|
|
dst += len;
|
|
dst_size -= len;
|
|
}
|
|
return src;
|
|
}
|
|
|
|
static const unsigned char *seq_decode_op1(SeqVideoContext *seq,
|
|
const unsigned char *src,
|
|
const unsigned char *src_end,
|
|
unsigned char *dst)
|
|
{
|
|
const unsigned char *color_table;
|
|
int b, i, len, bits;
|
|
GetBitContext gb;
|
|
unsigned char block[8 * 8];
|
|
|
|
if (src_end - src < 1)
|
|
return NULL;
|
|
len = *src++;
|
|
if (len & 0x80) {
|
|
switch (len & 3) {
|
|
case 1:
|
|
src = seq_unpack_rle_block(src, src_end, block, sizeof(block));
|
|
for (b = 0; b < 8; b++) {
|
|
memcpy(dst, &block[b * 8], 8);
|
|
dst += seq->frame->linesize[0];
|
|
}
|
|
break;
|
|
case 2:
|
|
src = seq_unpack_rle_block(src, src_end, block, sizeof(block));
|
|
for (i = 0; i < 8; i++) {
|
|
for (b = 0; b < 8; b++)
|
|
dst[b * seq->frame->linesize[0]] = block[i * 8 + b];
|
|
++dst;
|
|
}
|
|
break;
|
|
}
|
|
} else {
|
|
if (len <= 0)
|
|
return NULL;
|
|
bits = ff_log2_tab[len - 1] + 1;
|
|
if (src_end - src < len + 8 * bits)
|
|
return NULL;
|
|
color_table = src;
|
|
src += len;
|
|
init_get_bits(&gb, src, bits * 8 * 8); src += bits * 8;
|
|
for (b = 0; b < 8; b++) {
|
|
for (i = 0; i < 8; i++)
|
|
dst[i] = color_table[get_bits(&gb, bits)];
|
|
dst += seq->frame->linesize[0];
|
|
}
|
|
}
|
|
|
|
return src;
|
|
}
|
|
|
|
static const unsigned char *seq_decode_op2(SeqVideoContext *seq,
|
|
const unsigned char *src,
|
|
const unsigned char *src_end,
|
|
unsigned char *dst)
|
|
{
|
|
int i;
|
|
|
|
if (src_end - src < 8 * 8)
|
|
return NULL;
|
|
|
|
for (i = 0; i < 8; i++) {
|
|
memcpy(dst, src, 8);
|
|
src += 8;
|
|
dst += seq->frame->linesize[0];
|
|
}
|
|
|
|
return src;
|
|
}
|
|
|
|
static const unsigned char *seq_decode_op3(SeqVideoContext *seq,
|
|
const unsigned char *src,
|
|
const unsigned char *src_end,
|
|
unsigned char *dst)
|
|
{
|
|
int pos, offset;
|
|
|
|
do {
|
|
if (src_end - src < 2)
|
|
return NULL;
|
|
pos = *src++;
|
|
offset = ((pos >> 3) & 7) * seq->frame->linesize[0] + (pos & 7);
|
|
dst[offset] = *src++;
|
|
} while (!(pos & 0x80));
|
|
|
|
return src;
|
|
}
|
|
|
|
static int seqvideo_decode(SeqVideoContext *seq, const unsigned char *data, int data_size)
|
|
{
|
|
const unsigned char *data_end = data + data_size;
|
|
GetBitContext gb;
|
|
int flags, i, j, x, y, op;
|
|
unsigned char c[3];
|
|
unsigned char *dst;
|
|
uint32_t *palette;
|
|
|
|
flags = *data++;
|
|
|
|
if (flags & 1) {
|
|
palette = (uint32_t *)seq->frame->data[1];
|
|
if (data_end - data < 256 * 3)
|
|
return AVERROR_INVALIDDATA;
|
|
for (i = 0; i < 256; i++) {
|
|
for (j = 0; j < 3; j++, data++)
|
|
c[j] = (*data << 2) | (*data >> 4);
|
|
palette[i] = AV_RB24(c);
|
|
}
|
|
seq->frame->palette_has_changed = 1;
|
|
}
|
|
|
|
if (flags & 2) {
|
|
if (data_end - data < 128)
|
|
return AVERROR_INVALIDDATA;
|
|
init_get_bits(&gb, data, 128 * 8); data += 128;
|
|
for (y = 0; y < 128; y += 8)
|
|
for (x = 0; x < 256; x += 8) {
|
|
dst = &seq->frame->data[0][y * seq->frame->linesize[0] + x];
|
|
op = get_bits(&gb, 2);
|
|
switch (op) {
|
|
case 1:
|
|
data = seq_decode_op1(seq, data, data_end, dst);
|
|
break;
|
|
case 2:
|
|
data = seq_decode_op2(seq, data, data_end, dst);
|
|
break;
|
|
case 3:
|
|
data = seq_decode_op3(seq, data, data_end, dst);
|
|
break;
|
|
}
|
|
if (!data)
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static av_cold int seqvideo_decode_init(AVCodecContext *avctx)
|
|
{
|
|
SeqVideoContext *seq = avctx->priv_data;
|
|
|
|
seq->avctx = avctx;
|
|
avctx->pix_fmt = AV_PIX_FMT_PAL8;
|
|
|
|
seq->frame = av_frame_alloc();
|
|
if (!seq->frame)
|
|
return AVERROR(ENOMEM);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int seqvideo_decode_frame(AVCodecContext *avctx,
|
|
void *data, int *got_frame,
|
|
AVPacket *avpkt)
|
|
{
|
|
const uint8_t *buf = avpkt->data;
|
|
int buf_size = avpkt->size;
|
|
int ret;
|
|
|
|
SeqVideoContext *seq = avctx->priv_data;
|
|
|
|
if ((ret = ff_reget_buffer(avctx, seq->frame)) < 0) {
|
|
av_log(seq->avctx, AV_LOG_ERROR, "tiertexseqvideo: reget_buffer() failed\n");
|
|
return ret;
|
|
}
|
|
|
|
if (seqvideo_decode(seq, buf, buf_size))
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
if ((ret = av_frame_ref(data, seq->frame)) < 0)
|
|
return ret;
|
|
*got_frame = 1;
|
|
|
|
return buf_size;
|
|
}
|
|
|
|
static av_cold int seqvideo_decode_end(AVCodecContext *avctx)
|
|
{
|
|
SeqVideoContext *seq = avctx->priv_data;
|
|
|
|
av_frame_free(&seq->frame);
|
|
|
|
return 0;
|
|
}
|
|
|
|
AVCodec ff_tiertexseqvideo_decoder = {
|
|
.name = "tiertexseqvideo",
|
|
.long_name = NULL_IF_CONFIG_SMALL("Tiertex Limited SEQ video"),
|
|
.type = AVMEDIA_TYPE_VIDEO,
|
|
.id = AV_CODEC_ID_TIERTEXSEQVIDEO,
|
|
.priv_data_size = sizeof(SeqVideoContext),
|
|
.init = seqvideo_decode_init,
|
|
.close = seqvideo_decode_end,
|
|
.decode = seqvideo_decode_frame,
|
|
.capabilities = AV_CODEC_CAP_DR1,
|
|
};
|