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FFmpeg/libavcodec/vmdav.c
Kostya Shishkov 31980b6abd vmd: decode videos with no LZ buffer size provided - they might not need it
The buffer is used for an additional pass of frame compression, so videos
can be coded without ever using it (and some are coded so indeed, e.g. in
Woodruff and the Schnibble of Azimuth game).
2013-06-02 19:08:09 +02:00

676 lines
21 KiB
C

/*
* Sierra VMD Audio & Video Decoders
* Copyright (C) 2004 the ffmpeg project
*
* 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
* Sierra VMD audio & video decoders
* 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.
*
* The audio decoder, like the video decoder, expects each encoded data
* chunk to be prepended with the appropriate 16-byte frame information
* record from the VMD file. It does not require the 0x330-byte VMD file
* header, but it does need the audio setup parameters passed in through
* normal libavcodec API means.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "libavutil/channel_layout.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
/*
* Video Decoder
*/
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 void 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;
if (bytestream2_peek_le32(&gb) == 0x56781234) {
bytestream2_get_le32(&gb);
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 + 8 > d_end || bytestream2_get_bytes_left(&gb) < 8)
return;
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 + 1 > d_end || bytestream2_get_bytes_left(&gb) < 1)
return;
queue[qpos++] = *d++ = bytestream2_get_byte(&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 + chainlen > d_end)
return;
for (j = 0; j < chainlen; j++) {
*d = queue[chainofs++ & QUEUE_MASK];
queue[qpos++] = *d++;
qpos &= QUEUE_MASK;
}
dataleft -= chainlen;
}
tag >>= 1;
}
}
}
}
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 (pd + l > dest_end || bytestream2_get_bytes_left(&gb) < l)
return bytestream2_tell(&gb);
bytestream2_get_buffer(&gb, pd, l);
pd += l;
} else {
if (pd + l > dest_end || 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_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 ((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 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] = (r << 16) | (g << 8) | (b);
}
} else {
av_log(s->avctx, AV_LOG_ERROR, "Incomplete palette\n");
return AVERROR_INVALIDDATA;
}
s->size -= PALETTE_COUNT * 3 + 2;
}
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) {
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;
}
lz_unpack(gb.buffer, bytestream2_get_bytes_left(&gb),
s->unpack_buffer, s->unpack_buffer_size);
meth &= 0x7F;
bytestream2_init(&gb, s->unpack_buffer, 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_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,
"VMD video: 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 {
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,
"VMD video: 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_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, "VMD video: expected extradata size of %d\n",
VMD_HEADER_SIZE);
return -1;
}
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] = (r << 16) | (g << 8) | (b);
}
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) {
av_log(s->avctx, AV_LOG_ERROR, "VMD Video: get_buffer() failed\n");
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;
}
static av_cold int vmdvideo_decode_end(AVCodecContext *avctx)
{
VmdVideoContext *s = avctx->priv_data;
av_frame_unref(&s->prev_frame);
av_free(s->unpack_buffer);
return 0;
}
/*
* Audio Decoder
*/
#define BLOCK_TYPE_AUDIO 1
#define BLOCK_TYPE_INITIAL 2
#define BLOCK_TYPE_SILENCE 3
typedef struct VmdAudioContext {
int out_bps;
int chunk_size;
} VmdAudioContext;
static const uint16_t vmdaudio_table[128] = {
0x000, 0x008, 0x010, 0x020, 0x030, 0x040, 0x050, 0x060, 0x070, 0x080,
0x090, 0x0A0, 0x0B0, 0x0C0, 0x0D0, 0x0E0, 0x0F0, 0x100, 0x110, 0x120,
0x130, 0x140, 0x150, 0x160, 0x170, 0x180, 0x190, 0x1A0, 0x1B0, 0x1C0,
0x1D0, 0x1E0, 0x1F0, 0x200, 0x208, 0x210, 0x218, 0x220, 0x228, 0x230,
0x238, 0x240, 0x248, 0x250, 0x258, 0x260, 0x268, 0x270, 0x278, 0x280,
0x288, 0x290, 0x298, 0x2A0, 0x2A8, 0x2B0, 0x2B8, 0x2C0, 0x2C8, 0x2D0,
0x2D8, 0x2E0, 0x2E8, 0x2F0, 0x2F8, 0x300, 0x308, 0x310, 0x318, 0x320,
0x328, 0x330, 0x338, 0x340, 0x348, 0x350, 0x358, 0x360, 0x368, 0x370,
0x378, 0x380, 0x388, 0x390, 0x398, 0x3A0, 0x3A8, 0x3B0, 0x3B8, 0x3C0,
0x3C8, 0x3D0, 0x3D8, 0x3E0, 0x3E8, 0x3F0, 0x3F8, 0x400, 0x440, 0x480,
0x4C0, 0x500, 0x540, 0x580, 0x5C0, 0x600, 0x640, 0x680, 0x6C0, 0x700,
0x740, 0x780, 0x7C0, 0x800, 0x900, 0xA00, 0xB00, 0xC00, 0xD00, 0xE00,
0xF00, 0x1000, 0x1400, 0x1800, 0x1C00, 0x2000, 0x3000, 0x4000
};
static av_cold int vmdaudio_decode_init(AVCodecContext *avctx)
{
VmdAudioContext *s = avctx->priv_data;
if (avctx->channels < 1 || avctx->channels > 2) {
av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n");
return AVERROR(EINVAL);
}
if (avctx->block_align < 1) {
av_log(avctx, AV_LOG_ERROR, "invalid block align\n");
return AVERROR(EINVAL);
}
avctx->channel_layout = avctx->channels == 1 ? AV_CH_LAYOUT_MONO :
AV_CH_LAYOUT_STEREO;
if (avctx->bits_per_coded_sample == 16)
avctx->sample_fmt = AV_SAMPLE_FMT_S16;
else
avctx->sample_fmt = AV_SAMPLE_FMT_U8;
s->out_bps = av_get_bytes_per_sample(avctx->sample_fmt);
s->chunk_size = avctx->block_align + avctx->channels * (s->out_bps == 2);
av_log(avctx, AV_LOG_DEBUG, "%d channels, %d bits/sample, "
"block align = %d, sample rate = %d\n",
avctx->channels, avctx->bits_per_coded_sample, avctx->block_align,
avctx->sample_rate);
return 0;
}
static void decode_audio_s16(int16_t *out, const uint8_t *buf, int buf_size,
int channels)
{
int ch;
const uint8_t *buf_end = buf + buf_size;
int predictor[2];
int st = channels - 1;
/* decode initial raw sample */
for (ch = 0; ch < channels; ch++) {
predictor[ch] = (int16_t)AV_RL16(buf);
buf += 2;
*out++ = predictor[ch];
}
/* decode DPCM samples */
ch = 0;
while (buf < buf_end) {
uint8_t b = *buf++;
if (b & 0x80)
predictor[ch] -= vmdaudio_table[b & 0x7F];
else
predictor[ch] += vmdaudio_table[b];
predictor[ch] = av_clip_int16(predictor[ch]);
*out++ = predictor[ch];
ch ^= st;
}
}
static int vmdaudio_decode_frame(AVCodecContext *avctx, void *data,
int *got_frame_ptr, AVPacket *avpkt)
{
AVFrame *frame = data;
const uint8_t *buf = avpkt->data;
const uint8_t *buf_end;
int buf_size = avpkt->size;
VmdAudioContext *s = avctx->priv_data;
int block_type, silent_chunks, audio_chunks;
int ret;
uint8_t *output_samples_u8;
int16_t *output_samples_s16;
if (buf_size < 16) {
av_log(avctx, AV_LOG_WARNING, "skipping small junk packet\n");
*got_frame_ptr = 0;
return buf_size;
}
block_type = buf[6];
if (block_type < BLOCK_TYPE_AUDIO || block_type > BLOCK_TYPE_SILENCE) {
av_log(avctx, AV_LOG_ERROR, "unknown block type: %d\n", block_type);
return AVERROR(EINVAL);
}
buf += 16;
buf_size -= 16;
/* get number of silent chunks */
silent_chunks = 0;
if (block_type == BLOCK_TYPE_INITIAL) {
uint32_t flags;
if (buf_size < 4) {
av_log(avctx, AV_LOG_ERROR, "packet is too small\n");
return AVERROR(EINVAL);
}
flags = AV_RB32(buf);
silent_chunks = av_popcount(flags);
buf += 4;
buf_size -= 4;
} else if (block_type == BLOCK_TYPE_SILENCE) {
silent_chunks = 1;
buf_size = 0; // should already be zero but set it just to be sure
}
/* ensure output buffer is large enough */
audio_chunks = buf_size / s->chunk_size;
/* drop incomplete chunks */
buf_size = audio_chunks * s->chunk_size;
/* get output buffer */
frame->nb_samples = ((silent_chunks + audio_chunks) * avctx->block_align) /
avctx->channels;
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
return ret;
}
output_samples_u8 = frame->data[0];
output_samples_s16 = (int16_t *)frame->data[0];
/* decode silent chunks */
if (silent_chunks > 0) {
int silent_size = FFMIN(avctx->block_align * silent_chunks,
frame->nb_samples * avctx->channels);
if (s->out_bps == 2) {
memset(output_samples_s16, 0x00, silent_size * 2);
output_samples_s16 += silent_size;
} else {
memset(output_samples_u8, 0x80, silent_size);
output_samples_u8 += silent_size;
}
}
/* decode audio chunks */
if (audio_chunks > 0) {
buf_end = buf + (buf_size & ~(avctx->channels > 1));
while (buf + s->chunk_size <= buf_end) {
if (s->out_bps == 2) {
decode_audio_s16(output_samples_s16, buf, s->chunk_size,
avctx->channels);
output_samples_s16 += avctx->block_align;
} else {
memcpy(output_samples_u8, buf, s->chunk_size);
output_samples_u8 += avctx->block_align;
}
buf += s->chunk_size;
}
}
*got_frame_ptr = 1;
return avpkt->size;
}
/*
* Public Data Structures
*/
AVCodec ff_vmdvideo_decoder = {
.name = "vmdvideo",
.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 = CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("Sierra VMD video"),
};
AVCodec ff_vmdaudio_decoder = {
.name = "vmdaudio",
.type = AVMEDIA_TYPE_AUDIO,
.id = AV_CODEC_ID_VMDAUDIO,
.priv_data_size = sizeof(VmdAudioContext),
.init = vmdaudio_decode_init,
.decode = vmdaudio_decode_frame,
.capabilities = CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("Sierra VMD audio"),
};