/*
* Sierra VMD video decoder
* Copyright (c) 2004 The FFmpeg Project
*
* 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
*/
/**
* @file
* Sierra VMD video decoder
* by Vladimir "VAG" Gneushev (vagsoft at mail.ru)
* for more information on the Sierra VMD format, visit:
* http://www.pcisys.net/~melanson/codecs/
*
* The video decoder outputs PAL8 colorspace data. The decoder expects
* a 0x330-byte VMD file header to be transmitted via extradata during
* codec initialization. Each encoded frame that is sent to this decoder
* is expected to be prepended with the appropriate 16-byte frame
* information record from the VMD file.
*/
#include <string.h>
#include "libavutil/common.h"
#include "libavutil/intreadwrite.h"
#include "avcodec.h"
#include "internal.h"
#include "bytestream.h"
#define VMD_HEADER_SIZE 0x330
#define PALETTE_COUNT 256
typedef struct VmdVideoContext {
AVCodecContext *avctx;
AVFrame *prev_frame;
const unsigned char *buf;
int size;
unsigned char palette[PALETTE_COUNT * 4];
unsigned char *unpack_buffer;
int unpack_buffer_size;
int x_off, y_off;
} VmdVideoContext;
#define QUEUE_SIZE 0x1000
#define QUEUE_MASK 0x0FFF
static int lz_unpack(const unsigned char *src, int src_len,
unsigned char *dest, int dest_len)
{
unsigned char *d;
unsigned char *d_end;
unsigned char queue[QUEUE_SIZE];
unsigned int qpos;
unsigned int dataleft;
unsigned int chainofs;
unsigned int chainlen;
unsigned int speclen;
unsigned char tag;
unsigned int i, j;
GetByteContext gb;
bytestream2_init(&gb, src, src_len);
d = dest;
d_end = d + dest_len;
dataleft = bytestream2_get_le32(&gb);
memset(queue
, 0x20, QUEUE_SIZE
); if (bytestream2_get_bytes_left(&gb) < 4)
return AVERROR_INVALIDDATA;
if (bytestream2_peek_le32(&gb) == 0x56781234) {
bytestream2_skipu(&gb, 4);
qpos = 0x111;
speclen = 0xF + 3;
} else {
qpos = 0xFEE;
speclen = 100; /* no speclen */
}
while (dataleft > 0 && bytestream2_get_bytes_left(&gb) > 0) {
tag = bytestream2_get_byteu(&gb);
if ((tag == 0xFF) && (dataleft > 8)) {
if (d_end - d < 8 || bytestream2_get_bytes_left(&gb) < 8)
return AVERROR_INVALIDDATA;
for (i = 0; i < 8; i++) {
queue[qpos++] = *d++ = bytestream2_get_byteu(&gb);
qpos &= QUEUE_MASK;
}
dataleft -= 8;
} else {
for (i = 0; i < 8; i++) {
if (dataleft == 0)
break;
if (tag & 0x01) {
if (d_end - d < 1 || bytestream2_get_bytes_left(&gb) < 1)
return AVERROR_INVALIDDATA;
queue[qpos++] = *d++ = bytestream2_get_byteu(&gb);
qpos &= QUEUE_MASK;
dataleft--;
} else {
chainofs = bytestream2_get_byte(&gb);
chainofs |= ((bytestream2_peek_byte(&gb) & 0xF0) << 4);
chainlen = (bytestream2_get_byte(&gb) & 0x0F) + 3;
if (chainlen == speclen) {
chainlen = bytestream2_get_byte(&gb) + 0xF + 3;
}
if (d_end - d < chainlen)
return AVERROR_INVALIDDATA;
for (j = 0; j < chainlen; j++) {
*d = queue[chainofs++ & QUEUE_MASK];
queue[qpos++] = *d++;
qpos &= QUEUE_MASK;
}
dataleft -= chainlen;
}
tag >>= 1;
}
}
}
return d - dest;
}
static int rle_unpack(const unsigned char *src, unsigned char *dest,
int src_count, int src_size, int dest_len)
{
unsigned char *pd;
int i, l, used = 0;
unsigned char *dest_end = dest + dest_len;
GetByteContext gb;
uint16_t run_val;
bytestream2_init(&gb, src, src_size);
pd = dest;
if (src_count & 1) {
if (bytestream2_get_bytes_left(&gb) < 1)
return 0;
*pd++ = bytestream2_get_byteu(&gb);
used++;
}
do {
if (bytestream2_get_bytes_left(&gb) < 1)
break;
l = bytestream2_get_byteu(&gb);
if (l & 0x80) {
l = (l & 0x7F) * 2;
if (dest_end - pd < l || bytestream2_get_bytes_left(&gb) < l)
return bytestream2_tell(&gb);
bytestream2_get_bufferu(&gb, pd, l);
pd += l;
} else {
if (dest_end - pd < 2*l || bytestream2_get_bytes_left(&gb) < 2)
return bytestream2_tell(&gb);
run_val = bytestream2_get_ne16(&gb);
for (i = 0; i < l; i++) {
AV_WN16(pd, run_val);
pd += 2;
}
l *= 2;
}
used += l;
} while (used < src_count);
return bytestream2_tell(&gb);
}
static int vmd_decode(VmdVideoContext *s, AVFrame *frame)
{
int i;
unsigned int *palette32;
unsigned char r, g, b;
GetByteContext gb;
unsigned char meth;
unsigned char *dp; /* pointer to current frame */
unsigned char *pp; /* pointer to previous frame */
unsigned char len;
int ofs;
int frame_x, frame_y;
int frame_width, frame_height;
frame_x = AV_RL16(&s->buf[6]);
frame_y = AV_RL16(&s->buf[8]);
frame_width = AV_RL16(&s->buf[10]) - frame_x + 1;
frame_height = AV_RL16(&s->buf[12]) - frame_y + 1;
if ((frame_width == s->avctx->width && frame_height == s->avctx->height) &&
(frame_x || frame_y)) {
s->x_off = frame_x;
s->y_off = frame_y;
}
frame_x -= s->x_off;
frame_y -= s->y_off;
if (frame_x < 0 || frame_width < 0 ||
frame_x >= s->avctx->width ||
frame_width > s->avctx->width ||
frame_x + frame_width > s->avctx->width) {
av_log(s->avctx, AV_LOG_ERROR,
"Invalid horizontal range %d-%d\n",
frame_x, frame_width);
return AVERROR_INVALIDDATA;
}
if (frame_y < 0 || frame_height < 0 ||
frame_y >= s->avctx->height ||
frame_height > s->avctx->height ||
frame_y + frame_height > s->avctx->height) {
av_log(s->avctx, AV_LOG_ERROR,
"Invalid vertical range %d-%d\n",
frame_x, frame_width);
return AVERROR_INVALIDDATA;
}
/* if only a certain region will be updated, copy the entire previous
* frame before the decode */
if (s->prev_frame->data[0] &&
(frame_x || frame_y || (frame_width != s->avctx->width) ||
(frame_height != s->avctx->height))) {
memcpy(frame
->data
[0], s
->prev_frame
->data
[0], s->avctx->height * frame->linesize[0]);
}
/* check if there is a new palette */
bytestream2_init(&gb, s->buf + 16, s->size - 16);
if (s->buf[15] & 0x02) {
bytestream2_skip(&gb, 2);
palette32 = (unsigned int *)s->palette;
if (bytestream2_get_bytes_left(&gb) >= PALETTE_COUNT * 3) {
for (i = 0; i < PALETTE_COUNT; i++) {
r = bytestream2_get_byteu(&gb) * 4;
g = bytestream2_get_byteu(&gb) * 4;
b = bytestream2_get_byteu(&gb) * 4;
palette32[i] = 0xFFU << 24 | (r << 16) | (g << 8) | (b);
palette32[i] |= palette32[i] >> 6 & 0x30303;
}
} else {
av_log(s->avctx, AV_LOG_ERROR, "Incomplete palette\n");
return AVERROR_INVALIDDATA;
}
}
if (!s->size)
return 0;
/* originally UnpackFrame in VAG's code */
if (bytestream2_get_bytes_left(&gb) < 1)
return AVERROR_INVALIDDATA;
meth = bytestream2_get_byteu(&gb);
if (meth & 0x80) {
int size;
if (!s->unpack_buffer_size) {
av_log(s->avctx, AV_LOG_ERROR,
"Trying to unpack LZ-compressed frame with no LZ buffer\n");
return AVERROR_INVALIDDATA;
}
size = lz_unpack(gb.buffer, bytestream2_get_bytes_left(&gb),
s->unpack_buffer, s->unpack_buffer_size);
if (size < 0)
return size;
meth &= 0x7F;
bytestream2_init(&gb, s->unpack_buffer, size);
}
dp = &frame->data[0][frame_y * frame->linesize[0] + frame_x];
pp = &s->prev_frame->data[0][frame_y * s->prev_frame->linesize[0] + frame_x];
switch (meth) {
case 1:
for (i = 0; i < frame_height; i++) {
ofs = 0;
do {
len = bytestream2_get_byte(&gb);
if (len & 0x80) {
len = (len & 0x7F) + 1;
if (ofs + len > frame_width ||
bytestream2_get_bytes_left(&gb) < len)
return AVERROR_INVALIDDATA;
bytestream2_get_bufferu(&gb, &dp[ofs], len);
ofs += len;
} else {
/* interframe pixel copy */
if (ofs + len + 1 > frame_width || !s->prev_frame->data[0])
return AVERROR_INVALIDDATA;
memcpy(&dp
[ofs
], &pp
[ofs
], len
+ 1); ofs += len + 1;
}
} while (ofs < frame_width);
if (ofs > frame_width) {
av_log(s->avctx, AV_LOG_ERROR,
"offset > width (%d > %d)\n",
ofs, frame_width);
return AVERROR_INVALIDDATA;
}
dp += frame->linesize[0];
pp += s->prev_frame->linesize[0];
}
break;
case 2:
for (i = 0; i < frame_height; i++) {
bytestream2_get_buffer(&gb, dp, frame_width);
dp += frame->linesize[0];
pp += s->prev_frame->linesize[0];
}
break;
case 3:
for (i = 0; i < frame_height; i++) {
ofs = 0;
do {
len = bytestream2_get_byte(&gb);
if (len & 0x80) {
len = (len & 0x7F) + 1;
if (bytestream2_peek_byte(&gb) == 0xFF) {
int slen = len;
bytestream2_get_byte(&gb);
len = rle_unpack(gb.buffer, &dp[ofs],
len, bytestream2_get_bytes_left(&gb),
frame_width - ofs);
ofs += slen;
bytestream2_skip(&gb, len);
} else {
if (ofs + len > frame_width ||
bytestream2_get_bytes_left(&gb) < len)
return AVERROR_INVALIDDATA;
bytestream2_get_buffer(&gb, &dp[ofs], len);
ofs += len;
}
} else {
/* interframe pixel copy */
if (ofs + len + 1 > frame_width || !s->prev_frame->data[0])
return AVERROR_INVALIDDATA;
memcpy(&dp
[ofs
], &pp
[ofs
], len
+ 1); ofs += len + 1;
}
} while (ofs < frame_width);
if (ofs > frame_width) {
av_log(s->avctx, AV_LOG_ERROR,
"offset > width (%d > %d)\n",
ofs, frame_width);
return AVERROR_INVALIDDATA;
}
dp += frame->linesize[0];
pp += s->prev_frame->linesize[0];
}
break;
}
return 0;
}
static av_cold int vmdvideo_decode_end(AVCodecContext *avctx)
{
VmdVideoContext *s = avctx->priv_data;
av_frame_free(&s->prev_frame);
av_freep(&s->unpack_buffer);
s->unpack_buffer_size = 0;
return 0;
}
static av_cold int vmdvideo_decode_init(AVCodecContext *avctx)
{
VmdVideoContext *s = avctx->priv_data;
int i;
unsigned int *palette32;
int palette_index = 0;
unsigned char r, g, b;
unsigned char *vmd_header;
unsigned char *raw_palette;
s->avctx = avctx;
avctx->pix_fmt = AV_PIX_FMT_PAL8;
/* make sure the VMD header made it */
if (s->avctx->extradata_size != VMD_HEADER_SIZE) {
av_log(s->avctx, AV_LOG_ERROR, "expected extradata size of %d\n",
VMD_HEADER_SIZE);
return AVERROR_INVALIDDATA;
}
vmd_header = (unsigned char *)avctx->extradata;
s->unpack_buffer_size = AV_RL32(&vmd_header[800]);
if (s->unpack_buffer_size) {
s->unpack_buffer = av_malloc(s->unpack_buffer_size);
if (!s->unpack_buffer)
return AVERROR(ENOMEM);
}
/* load up the initial palette */
raw_palette = &vmd_header[28];
palette32 = (unsigned int *)s->palette;
for (i = 0; i < PALETTE_COUNT; i++) {
r = raw_palette[palette_index++] * 4;
g = raw_palette[palette_index++] * 4;
b = raw_palette[palette_index++] * 4;
palette32[i] = 0xFFU << 24 | (r << 16) | (g << 8) | (b);
palette32[i] |= palette32[i] >> 6 & 0x30303;
}
s->prev_frame = av_frame_alloc();
if (!s->prev_frame) {
vmdvideo_decode_end(avctx);
return AVERROR(ENOMEM);
}
return 0;
}
static int vmdvideo_decode_frame(AVCodecContext *avctx,
void *data, int *got_frame,
AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
VmdVideoContext *s = avctx->priv_data;
AVFrame *frame = data;
int ret;
s->buf = buf;
s->size = buf_size;
if (buf_size < 16)
return AVERROR_INVALIDDATA;
if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
return ret;
if ((ret = vmd_decode(s, frame)) < 0)
return ret;
/* make the palette available on the way out */
memcpy(frame
->data
[1], s
->palette
, PALETTE_COUNT
* 4);
/* shuffle frames */
av_frame_unref(s->prev_frame);
if ((ret = av_frame_ref(s->prev_frame, frame)) < 0)
return ret;
*got_frame = 1;
/* report that the buffer was completely consumed */
return buf_size;
}
AVCodec ff_vmdvideo_decoder = {
.name = "vmdvideo",
.long_name = NULL_IF_CONFIG_SMALL("Sierra VMD video"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_VMDVIDEO,
.priv_data_size = sizeof(VmdVideoContext),
.init = vmdvideo_decode_init,
.close = vmdvideo_decode_end,
.decode = vmdvideo_decode_frame,
.capabilities = AV_CODEC_CAP_DR1,
};