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/*
* Interplay MVE Video Decoder
* Copyright (C) 2003 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
* Interplay MVE Video Decoder by Mike Melanson (melanson@pcisys.net)
* For more information about the Interplay MVE format, visit:
* http://www.pcisys.net/~melanson/codecs/interplay-mve.txt
* This code is written in such a way that the identifiers match up
* with the encoding descriptions in the document.
*
* This decoder presently only supports a PAL8 output colorspace.
*
* An Interplay video frame consists of 2 parts: The decoding map and
* the video data. A demuxer must load these 2 parts together in a single
* buffer before sending it through the stream to this decoder.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "avcodec.h"
#include "bytestream.h"
#include "dsputil.h"
#define ALT_BITSTREAM_READER_LE
#include "get_bits.h"
#define PALETTE_COUNT 256
/* debugging support */
#define DEBUG_INTERPLAY 0
#if DEBUG_INTERPLAY
#define debug_interplay(x,...) av_log(NULL, AV_LOG_DEBUG, x, __VA_ARGS__)
#else
static inline void debug_interplay(const char *format, ...) { }
#endif
typedef struct IpvideoContext {
AVCodecContext *avctx;
DSPContext dsp;
AVFrame second_last_frame;
AVFrame last_frame;
AVFrame current_frame;
const unsigned char *decoding_map;
int decoding_map_size;
const unsigned char *buf;
int size;
int is_16bpp;
const unsigned char *stream_ptr;
const unsigned char *stream_end;
const uint8_t *mv_ptr;
const uint8_t *mv_end;
unsigned char *pixel_ptr;
int line_inc;
int stride;
int upper_motion_limit_offset;
} IpvideoContext;
#define CHECK_STREAM_PTR(stream_ptr, stream_end, n) \
if (stream_end - stream_ptr < n) { \
av_log(s->avctx, AV_LOG_ERROR, "Interplay video warning: stream_ptr out of bounds (%p >= %p)\n", \
stream_ptr + n, stream_end); \
return -1; \
}
static int copy_from(IpvideoContext *s, AVFrame *src, int delta_x, int delta_y)
{
int current_offset = s->pixel_ptr - s->current_frame.data[0];
int motion_offset = current_offset + delta_y * s->current_frame.linesize[0]
+ delta_x * (1 + s->is_16bpp);
if (motion_offset < 0) {
av_log(s->avctx, AV_LOG_ERROR, " Interplay video: motion offset < 0 (%d)\n", motion_offset);
return -1;
} else if (motion_offset > s->upper_motion_limit_offset) {
av_log(s->avctx, AV_LOG_ERROR, " Interplay video: motion offset above limit (%d >= %d)\n",
motion_offset, s->upper_motion_limit_offset);
return -1;
}
s->dsp.put_pixels_tab[!s->is_16bpp][0](s->pixel_ptr, src->data[0] + motion_offset,
s->current_frame.linesize[0], 8);
return 0;
}
static int ipvideo_decode_block_opcode_0x0(IpvideoContext *s)
{
return copy_from(s, &s->last_frame, 0, 0);
}
static int ipvideo_decode_block_opcode_0x1(IpvideoContext *s)
{
return copy_from(s, &s->second_last_frame, 0, 0);
}
static int ipvideo_decode_block_opcode_0x2(IpvideoContext *s)
{
unsigned char B;
int x, y;
/* copy block from 2 frames ago using a motion vector; need 1 more byte */
if (!s->is_16bpp) {
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 1);
B = *s->stream_ptr++;
} else {
CHECK_STREAM_PTR(s->mv_ptr, s->mv_end, 1);
B = *s->mv_ptr++;
}
if (B < 56) {
x = 8 + (B % 7);
y = B / 7;
} else {
x = -14 + ((B - 56) % 29);
y = 8 + ((B - 56) / 29);
}
debug_interplay (" motion byte = %d, (x, y) = (%d, %d)\n", B, x, y);
return copy_from(s, &s->second_last_frame, x, y);
}
static int ipvideo_decode_block_opcode_0x3(IpvideoContext *s)
{
unsigned char B;
int x, y;
/* copy 8x8 block from current frame from an up/left block */
/* need 1 more byte for motion */
if (!s->is_16bpp) {
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 1);
B = *s->stream_ptr++;
} else {
CHECK_STREAM_PTR(s->mv_ptr, s->mv_end, 1);
B = *s->mv_ptr++;
}
if (B < 56) {
x = -(8 + (B % 7));
y = -(B / 7);
} else {
x = -(-14 + ((B - 56) % 29));
y = -( 8 + ((B - 56) / 29));
}
debug_interplay (" motion byte = %d, (x, y) = (%d, %d)\n", B, x, y);
return copy_from(s, &s->current_frame, x, y);
}
static int ipvideo_decode_block_opcode_0x4(IpvideoContext *s)
{
int x, y;
unsigned char B, BL, BH;
/* copy a block from the previous frame; need 1 more byte */
if (!s->is_16bpp) {
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 1);
B = *s->stream_ptr++;
} else {
CHECK_STREAM_PTR(s->mv_ptr, s->mv_end, 1);
B = *s->mv_ptr++;
}
BL = B & 0x0F;
BH = (B >> 4) & 0x0F;
x = -8 + BL;
y = -8 + BH;
debug_interplay (" motion byte = %d, (x, y) = (%d, %d)\n", B, x, y);
return copy_from(s, &s->last_frame, x, y);
}
static int ipvideo_decode_block_opcode_0x5(IpvideoContext *s)
{
signed char x, y;
/* copy a block from the previous frame using an expanded range;
* need 2 more bytes */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 2);
x = *s->stream_ptr++;
y = *s->stream_ptr++;
debug_interplay (" motion bytes = %d, %d\n", x, y);
return copy_from(s, &s->last_frame, x, y);
}
static int ipvideo_decode_block_opcode_0x6(IpvideoContext *s)
{
/* mystery opcode? skip multiple blocks? */
av_log(s->avctx, AV_LOG_ERROR, " Interplay video: Help! Mystery opcode 0x6 seen\n");
/* report success */
return 0;
}
static int ipvideo_decode_block_opcode_0x7(IpvideoContext *s)
{
int x, y;
unsigned char P[2];
unsigned int flags;
/* 2-color encoding */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 2);
P[0] = *s->stream_ptr++;
P[1] = *s->stream_ptr++;
if (P[0] <= P[1]) {
/* need 8 more bytes from the stream */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 8);
for (y = 0; y < 8; y++) {
flags = *s->stream_ptr++ | 0x100;
for (; flags != 1; flags >>= 1)
*s->pixel_ptr++ = P[flags & 1];
s->pixel_ptr += s->line_inc;
}
} else {
/* need 2 more bytes from the stream */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 2);
flags = bytestream_get_le16(&s->stream_ptr);
for (y = 0; y < 8; y += 2) {
for (x = 0; x < 8; x += 2, flags >>= 1) {
s->pixel_ptr[x ] =
s->pixel_ptr[x + 1 ] =
s->pixel_ptr[x + s->stride] =
s->pixel_ptr[x + 1 + s->stride] = P[flags & 1];
}
s->pixel_ptr += s->stride * 2;
}
}
/* report success */
return 0;
}
static int ipvideo_decode_block_opcode_0x8(IpvideoContext *s)
{
int x, y;
unsigned char P[2];
unsigned int flags = 0;
/* 2-color encoding for each 4x4 quadrant, or 2-color encoding on
* either top and bottom or left and right halves */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 2);
P[0] = *s->stream_ptr++;
P[1] = *s->stream_ptr++;
if (P[0] <= P[1]) {
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 14);
s->stream_ptr -= 2;
for (y = 0; y < 16; y++) {
// new values for each 4x4 block
if (!(y & 3)) {
P[0] = *s->stream_ptr++; P[1] = *s->stream_ptr++;
flags = bytestream_get_le16(&s->stream_ptr);
}
for (x = 0; x < 4; x++, flags >>= 1)
*s->pixel_ptr++ = P[flags & 1];
s->pixel_ptr += s->stride - 4;
// switch to right half
if (y == 7) s->pixel_ptr -= 8 * s->stride - 4;
}
} else {
/* need 10 more bytes */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 10);
if (s->stream_ptr[4] <= s->stream_ptr[5]) {
flags = bytestream_get_le32(&s->stream_ptr);
/* vertical split; left & right halves are 2-color encoded */
for (y = 0; y < 16; y++) {
for (x = 0; x < 4; x++, flags >>= 1)
*s->pixel_ptr++ = P[flags & 1];
s->pixel_ptr += s->stride - 4;
// switch to right half
if (y == 7) {
s->pixel_ptr -= 8 * s->stride - 4;
P[0] = *s->stream_ptr++; P[1] = *s->stream_ptr++;
flags = bytestream_get_le32(&s->stream_ptr);
}
}
} else {
/* horizontal split; top & bottom halves are 2-color encoded */
for (y = 0; y < 8; y++) {
if (y == 4) {
P[0] = *s->stream_ptr++;
P[1] = *s->stream_ptr++;
}
flags = *s->stream_ptr++ | 0x100;
for (; flags != 1; flags >>= 1)
*s->pixel_ptr++ = P[flags & 1];
s->pixel_ptr += s->line_inc;
}
}
}
/* report success */
return 0;
}
static int ipvideo_decode_block_opcode_0x9(IpvideoContext *s)
{
int x, y;
unsigned char P[4];
/* 4-color encoding */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 4);
memcpy(P, s->stream_ptr, 4);
s->stream_ptr += 4;
if (P[0] <= P[1]) {
if (P[2] <= P[3]) {
/* 1 of 4 colors for each pixel, need 16 more bytes */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 16);
for (y = 0; y < 8; y++) {
/* get the next set of 8 2-bit flags */
int flags = bytestream_get_le16(&s->stream_ptr);
for (x = 0; x < 8; x++, flags >>= 2)
*s->pixel_ptr++ = P[flags & 0x03];
s->pixel_ptr += s->line_inc;
}
} else {
uint32_t flags;
/* 1 of 4 colors for each 2x2 block, need 4 more bytes */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 4);
flags = bytestream_get_le32(&s->stream_ptr);
for (y = 0; y < 8; y += 2) {
for (x = 0; x < 8; x += 2, flags >>= 2) {
s->pixel_ptr[x ] =
s->pixel_ptr[x + 1 ] =
s->pixel_ptr[x + s->stride] =
s->pixel_ptr[x + 1 + s->stride] = P[flags & 0x03];
}
s->pixel_ptr += s->stride * 2;
}
}
} else {
uint64_t flags;
/* 1 of 4 colors for each 2x1 or 1x2 block, need 8 more bytes */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 8);
flags = bytestream_get_le64(&s->stream_ptr);
if (P[2] <= P[3]) {
for (y = 0; y < 8; y++) {
for (x = 0; x < 8; x += 2, flags >>= 2) {
s->pixel_ptr[x ] =
s->pixel_ptr[x + 1] = P[flags & 0x03];
}
s->pixel_ptr += s->stride;
}
} else {
for (y = 0; y < 8; y += 2) {
for (x = 0; x < 8; x++, flags >>= 2) {
s->pixel_ptr[x ] =
s->pixel_ptr[x + s->stride] = P[flags & 0x03];
}
s->pixel_ptr += s->stride * 2;
}
}
}
/* report success */
return 0;
}
static int ipvideo_decode_block_opcode_0xA(IpvideoContext *s)
{
int x, y;
unsigned char P[4];
int flags = 0;
/* 4-color encoding for each 4x4 quadrant, or 4-color encoding on
* either top and bottom or left and right halves */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 24);
if (s->stream_ptr[0] <= s->stream_ptr[1]) {
/* 4-color encoding for each quadrant; need 32 bytes */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 32);
for (y = 0; y < 16; y++) {
// new values for each 4x4 block
if (!(y & 3)) {
memcpy(P, s->stream_ptr, 4);
s->stream_ptr += 4;
flags = bytestream_get_le32(&s->stream_ptr);
}
for (x = 0; x < 4; x++, flags >>= 2)
*s->pixel_ptr++ = P[flags & 0x03];
s->pixel_ptr += s->stride - 4;
// switch to right half
if (y == 7) s->pixel_ptr -= 8 * s->stride - 4;
}
} else {
// vertical split?
int vert = s->stream_ptr[12] <= s->stream_ptr[13];
uint64_t flags = 0;
/* 4-color encoding for either left and right or top and bottom
* halves */
for (y = 0; y < 16; y++) {
// load values for each half
if (!(y & 7)) {
memcpy(P, s->stream_ptr, 4);
s->stream_ptr += 4;
flags = bytestream_get_le64(&s->stream_ptr);
}
for (x = 0; x < 4; x++, flags >>= 2)
*s->pixel_ptr++ = P[flags & 0x03];
if (vert) {
s->pixel_ptr += s->stride - 4;
// switch to right half
if (y == 7) s->pixel_ptr -= 8 * s->stride - 4;
} else if (y & 1) s->pixel_ptr += s->line_inc;
}
}
/* report success */
return 0;
}
static int ipvideo_decode_block_opcode_0xB(IpvideoContext *s)
{
int y;
/* 64-color encoding (each pixel in block is a different color) */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 64);
for (y = 0; y < 8; y++) {
memcpy(s->pixel_ptr, s->stream_ptr, 8);
s->stream_ptr += 8;
s->pixel_ptr += s->stride;
}
/* report success */
return 0;
}
static int ipvideo_decode_block_opcode_0xC(IpvideoContext *s)
{
int x, y;
/* 16-color block encoding: each 2x2 block is a different color */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 16);
for (y = 0; y < 8; y += 2) {
for (x = 0; x < 8; x += 2) {
s->pixel_ptr[x ] =
s->pixel_ptr[x + 1 ] =
s->pixel_ptr[x + s->stride] =
s->pixel_ptr[x + 1 + s->stride] = *s->stream_ptr++;
}
s->pixel_ptr += s->stride * 2;
}
/* report success */
return 0;
}
static int ipvideo_decode_block_opcode_0xD(IpvideoContext *s)
{
int y;
unsigned char P[2];
/* 4-color block encoding: each 4x4 block is a different color */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 4);
for (y = 0; y < 8; y++) {
if (!(y & 3)) {
P[0] = *s->stream_ptr++;
P[1] = *s->stream_ptr++;
}
memset(s->pixel_ptr, P[0], 4);
memset(s->pixel_ptr + 4, P[1], 4);
s->pixel_ptr += s->stride;
}
/* report success */
return 0;
}
static int ipvideo_decode_block_opcode_0xE(IpvideoContext *s)
{
int y;
unsigned char pix;
/* 1-color encoding: the whole block is 1 solid color */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 1);
pix = *s->stream_ptr++;
for (y = 0; y < 8; y++) {
memset(s->pixel_ptr, pix, 8);
s->pixel_ptr += s->stride;
}
/* report success */
return 0;
}
static int ipvideo_decode_block_opcode_0xF(IpvideoContext *s)
{
int x, y;
unsigned char sample[2];
/* dithered encoding */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 2);
sample[0] = *s->stream_ptr++;
sample[1] = *s->stream_ptr++;
for (y = 0; y < 8; y++) {
for (x = 0; x < 8; x += 2) {
*s->pixel_ptr++ = sample[ y & 1 ];
*s->pixel_ptr++ = sample[!(y & 1)];
}
s->pixel_ptr += s->line_inc;
}
/* report success */
return 0;
}
static int ipvideo_decode_block_opcode_0x6_16(IpvideoContext *s)
{
signed char x, y;
/* copy a block from the second last frame using an expanded range */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 2);
x = *s->stream_ptr++;
y = *s->stream_ptr++;
debug_interplay (" motion bytes = %d, %d\n", x, y);
return copy_from(s, &s->second_last_frame, x, y);
}
static int ipvideo_decode_block_opcode_0x7_16(IpvideoContext *s)
{
int x, y;
uint16_t P[2];
unsigned int flags;
uint16_t *pixel_ptr = (uint16_t*)s->pixel_ptr;
/* 2-color encoding */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 4);
P[0] = bytestream_get_le16(&s->stream_ptr);
P[1] = bytestream_get_le16(&s->stream_ptr);
if (!(P[0] & 0x8000)) {
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 8);
for (y = 0; y < 8; y++) {
flags = *s->stream_ptr++ | 0x100;
for (; flags != 1; flags >>= 1)
*pixel_ptr++ = P[flags & 1];
pixel_ptr += s->line_inc;
}
} else {
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 2);
flags = bytestream_get_le16(&s->stream_ptr);
for (y = 0; y < 8; y += 2) {
for (x = 0; x < 8; x += 2, flags >>= 1) {
pixel_ptr[x ] =
pixel_ptr[x + 1 ] =
pixel_ptr[x + s->stride] =
pixel_ptr[x + 1 + s->stride] = P[flags & 1];
}
pixel_ptr += s->stride * 2;
}
}
return 0;
}
static int ipvideo_decode_block_opcode_0x8_16(IpvideoContext *s)
{
int x, y;
uint16_t P[2];
unsigned int flags = 0;
uint16_t *pixel_ptr = (uint16_t*)s->pixel_ptr;
/* 2-color encoding for each 4x4 quadrant, or 2-color encoding on
* either top and bottom or left and right halves */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 4);
P[0] = bytestream_get_le16(&s->stream_ptr);
P[1] = bytestream_get_le16(&s->stream_ptr);
if (!(P[0] & 0x8000)) {
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 24);
s->stream_ptr -= 4;
for (y = 0; y < 16; y++) {
// new values for each 4x4 block
if (!(y & 3)) {
P[0] = bytestream_get_le16(&s->stream_ptr);
P[1] = bytestream_get_le16(&s->stream_ptr);
flags = bytestream_get_le16(&s->stream_ptr);
}
for (x = 0; x < 4; x++, flags >>= 1)
*pixel_ptr++ = P[flags & 1];
pixel_ptr += s->stride - 4;
// switch to right half
if (y == 7) pixel_ptr -= 8 * s->stride - 4;
}
} else {
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 12);
if (!(AV_RL16(s->stream_ptr + 4) & 0x8000)) {
flags = bytestream_get_le32(&s->stream_ptr);
/* vertical split; left & right halves are 2-color encoded */
for (y = 0; y < 16; y++) {
for (x = 0; x < 4; x++, flags >>= 1)
*pixel_ptr++ = P[flags & 1];
pixel_ptr += s->stride - 4;
// switch to right half
if (y == 7) {
pixel_ptr -= 8 * s->stride - 4;
P[0] = bytestream_get_le16(&s->stream_ptr);
P[1] = bytestream_get_le16(&s->stream_ptr);
flags = bytestream_get_le32(&s->stream_ptr);
}
}
} else {
/* horizontal split; top & bottom halves are 2-color encoded */
for (y = 0; y < 8; y++) {
if (y == 4) {
P[0] = bytestream_get_le16(&s->stream_ptr);
P[1] = bytestream_get_le16(&s->stream_ptr);
}
flags = *s->stream_ptr++ | 0x100;
for (; flags != 1; flags >>= 1)
*pixel_ptr++ = P[flags & 1];
pixel_ptr += s->line_inc;
}
}
}
/* report success */
return 0;
}
static int ipvideo_decode_block_opcode_0x9_16(IpvideoContext *s)
{
int x, y;
uint16_t P[4];
uint16_t *pixel_ptr = (uint16_t*)s->pixel_ptr;
/* 4-color encoding */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 8);
for (x = 0; x < 4; x++)
P[x] = bytestream_get_le16(&s->stream_ptr);
if (!(P[0] & 0x8000)) {
if (!(P[2] & 0x8000)) {
/* 1 of 4 colors for each pixel */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 16);
for (y = 0; y < 8; y++) {
/* get the next set of 8 2-bit flags */
int flags = bytestream_get_le16(&s->stream_ptr);
for (x = 0; x < 8; x++, flags >>= 2)
*pixel_ptr++ = P[flags & 0x03];
pixel_ptr += s->line_inc;
}
} else {
uint32_t flags;
/* 1 of 4 colors for each 2x2 block */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 4);
flags = bytestream_get_le32(&s->stream_ptr);
for (y = 0; y < 8; y += 2) {
for (x = 0; x < 8; x += 2, flags >>= 2) {
pixel_ptr[x ] =
pixel_ptr[x + 1 ] =
pixel_ptr[x + s->stride] =
pixel_ptr[x + 1 + s->stride] = P[flags & 0x03];
}
pixel_ptr += s->stride * 2;
}
}
} else {
uint64_t flags;
/* 1 of 4 colors for each 2x1 or 1x2 block */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 8);
flags = bytestream_get_le64(&s->stream_ptr);
if (!(P[2] & 0x8000)) {
for (y = 0; y < 8; y++) {
for (x = 0; x < 8; x += 2, flags >>= 2) {
pixel_ptr[x ] =
pixel_ptr[x + 1] = P[flags & 0x03];
}
pixel_ptr += s->stride;
}
} else {
for (y = 0; y < 8; y += 2) {
for (x = 0; x < 8; x++, flags >>= 2) {
pixel_ptr[x ] =
pixel_ptr[x + s->stride] = P[flags & 0x03];
}
pixel_ptr += s->stride * 2;
}
}
}
/* report success */
return 0;
}
static int ipvideo_decode_block_opcode_0xA_16(IpvideoContext *s)
{
int x, y;
uint16_t P[4];
int flags = 0;
uint16_t *pixel_ptr = (uint16_t*)s->pixel_ptr;
/* 4-color encoding for each 4x4 quadrant, or 4-color encoding on
* either top and bottom or left and right halves */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 24);
if (!(AV_RL16(s->stream_ptr) & 0x8000)) {
/* 4-color encoding for each quadrant */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 48);
for (y = 0; y < 16; y++) {
// new values for each 4x4 block
if (!(y & 3)) {
for (x = 0; x < 4; x++)
P[x] = bytestream_get_le16(&s->stream_ptr);
flags = bytestream_get_le32(&s->stream_ptr);
}
for (x = 0; x < 4; x++, flags >>= 2)
*pixel_ptr++ = P[flags & 0x03];
pixel_ptr += s->stride - 4;
// switch to right half
if (y == 7) pixel_ptr -= 8 * s->stride - 4;
}
} else {
// vertical split?
int vert = !(AV_RL16(s->stream_ptr + 16) & 0x8000);
uint64_t flags = 0;
/* 4-color encoding for either left and right or top and bottom
* halves */
for (y = 0; y < 16; y++) {
// load values for each half
if (!(y & 7)) {
for (x = 0; x < 4; x++)
P[x] = bytestream_get_le16(&s->stream_ptr);
flags = bytestream_get_le64(&s->stream_ptr);
}
for (x = 0; x < 4; x++, flags >>= 2)
*pixel_ptr++ = P[flags & 0x03];
if (vert) {
pixel_ptr += s->stride - 4;
// switch to right half
if (y == 7) pixel_ptr -= 8 * s->stride - 4;
} else if (y & 1) pixel_ptr += s->line_inc;
}
}
/* report success */
return 0;
}
static int ipvideo_decode_block_opcode_0xB_16(IpvideoContext *s)
{
int x, y;
uint16_t *pixel_ptr = (uint16_t*)s->pixel_ptr;
/* 64-color encoding (each pixel in block is a different color) */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 128);
for (y = 0; y < 8; y++) {
for (x = 0; x < 8; x++)
pixel_ptr[x] = bytestream_get_le16(&s->stream_ptr);
pixel_ptr += s->stride;
}
/* report success */
return 0;
}
static int ipvideo_decode_block_opcode_0xC_16(IpvideoContext *s)
{
int x, y;
uint16_t *pixel_ptr = (uint16_t*)s->pixel_ptr;
/* 16-color block encoding: each 2x2 block is a different color */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 32);
for (y = 0; y < 8; y += 2) {
for (x = 0; x < 8; x += 2) {
pixel_ptr[x ] =
pixel_ptr[x + 1 ] =
pixel_ptr[x + s->stride] =
pixel_ptr[x + 1 + s->stride] = bytestream_get_le16(&s->stream_ptr);
}
pixel_ptr += s->stride * 2;
}
/* report success */
return 0;
}
static int ipvideo_decode_block_opcode_0xD_16(IpvideoContext *s)
{
int x, y;
uint16_t P[2];
uint16_t *pixel_ptr = (uint16_t*)s->pixel_ptr;
/* 4-color block encoding: each 4x4 block is a different color */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 8);
for (y = 0; y < 8; y++) {
if (!(y & 3)) {
P[0] = bytestream_get_le16(&s->stream_ptr);
P[1] = bytestream_get_le16(&s->stream_ptr);
}
for (x = 0; x < 8; x++)
pixel_ptr[x] = P[x >> 2];
pixel_ptr += s->stride;
}
/* report success */
return 0;
}
static int ipvideo_decode_block_opcode_0xE_16(IpvideoContext *s)
{
int x, y;
uint16_t pix;
uint16_t *pixel_ptr = (uint16_t*)s->pixel_ptr;
/* 1-color encoding: the whole block is 1 solid color */
CHECK_STREAM_PTR(s->stream_ptr, s->stream_end, 2);
pix = bytestream_get_le16(&s->stream_ptr);
for (y = 0; y < 8; y++) {
for (x = 0; x < 8; x++)
pixel_ptr[x] = pix;
pixel_ptr += s->stride;
}
/* report success */
return 0;
}
static int (* const ipvideo_decode_block[])(IpvideoContext *s) = {
ipvideo_decode_block_opcode_0x0, ipvideo_decode_block_opcode_0x1,
ipvideo_decode_block_opcode_0x2, ipvideo_decode_block_opcode_0x3,
ipvideo_decode_block_opcode_0x4, ipvideo_decode_block_opcode_0x5,
ipvideo_decode_block_opcode_0x6, ipvideo_decode_block_opcode_0x7,
ipvideo_decode_block_opcode_0x8, ipvideo_decode_block_opcode_0x9,
ipvideo_decode_block_opcode_0xA, ipvideo_decode_block_opcode_0xB,
ipvideo_decode_block_opcode_0xC, ipvideo_decode_block_opcode_0xD,
ipvideo_decode_block_opcode_0xE, ipvideo_decode_block_opcode_0xF,
};
static int (* const ipvideo_decode_block16[])(IpvideoContext *s) = {
ipvideo_decode_block_opcode_0x0, ipvideo_decode_block_opcode_0x1,
ipvideo_decode_block_opcode_0x2, ipvideo_decode_block_opcode_0x3,
ipvideo_decode_block_opcode_0x4, ipvideo_decode_block_opcode_0x5,
ipvideo_decode_block_opcode_0x6_16, ipvideo_decode_block_opcode_0x7_16,
ipvideo_decode_block_opcode_0x8_16, ipvideo_decode_block_opcode_0x9_16,
ipvideo_decode_block_opcode_0xA_16, ipvideo_decode_block_opcode_0xB_16,
ipvideo_decode_block_opcode_0xC_16, ipvideo_decode_block_opcode_0xD_16,
ipvideo_decode_block_opcode_0xE_16, ipvideo_decode_block_opcode_0x1,
};
static void ipvideo_decode_opcodes(IpvideoContext *s)
{
int x, y;
unsigned char opcode;
int ret;
static int frame = 0;
GetBitContext gb;
debug_interplay("------------------ frame %d\n", frame);
frame++;
if (!s->is_16bpp) {
/* this is PAL8, so make the palette available */
memcpy(s->current_frame.data[1], s->avctx->palctrl->palette, PALETTE_COUNT * 4);
s->stride = s->current_frame.linesize[0];
s->stream_ptr = s->buf + 14; /* data starts 14 bytes in */
s->stream_end = s->buf + s->size;
} else {
s->stride = s->current_frame.linesize[0] >> 1;
s->stream_ptr = s->buf + 16;
s->stream_end =
s->mv_ptr = s->buf + 14 + AV_RL16(s->buf+14);
s->mv_end = s->buf + s->size;
}
s->line_inc = s->stride - 8;
s->upper_motion_limit_offset = (s->avctx->height - 8) * s->current_frame.linesize[0]
+ (s->avctx->width - 8) * (1 + s->is_16bpp);
init_get_bits(&gb, s->decoding_map, s->decoding_map_size * 8);
for (y = 0; y < s->avctx->height; y += 8) {
for (x = 0; x < s->avctx->width; x += 8) {
opcode = get_bits(&gb, 4);
debug_interplay(" block @ (%3d, %3d): encoding 0x%X, data ptr @ %p\n",
x, y, opcode, s->stream_ptr);
if (!s->is_16bpp) {
s->pixel_ptr = s->current_frame.data[0] + x
+ y*s->current_frame.linesize[0];
ret = ipvideo_decode_block[opcode](s);
} else {
s->pixel_ptr = s->current_frame.data[0] + x*2
+ y*s->current_frame.linesize[0];
ret = ipvideo_decode_block16[opcode](s);
}
if (ret != 0) {
av_log(s->avctx, AV_LOG_ERROR, " Interplay video: decode problem on frame %d, @ block (%d, %d)\n",
frame, x, y);
return;
}
}
}
if (s->stream_end - s->stream_ptr > 1) {
av_log(s->avctx, AV_LOG_ERROR, " Interplay video: decode finished with %td bytes left over\n",
s->stream_end - s->stream_ptr);
}
}
static av_cold int ipvideo_decode_init(AVCodecContext *avctx)
{
IpvideoContext *s = avctx->priv_data;
s->avctx = avctx;
s->is_16bpp = avctx->bits_per_coded_sample == 16;
avctx->pix_fmt = s->is_16bpp ? PIX_FMT_RGB555 : PIX_FMT_PAL8;
if (!s->is_16bpp && s->avctx->palctrl == NULL) {
av_log(avctx, AV_LOG_ERROR, " Interplay video: palette expected.\n");
return -1;
}
dsputil_init(&s->dsp, avctx);
/* decoding map contains 4 bits of information per 8x8 block */
s->decoding_map_size = avctx->width * avctx->height / (8 * 8 * 2);
s->current_frame.data[0] = s->last_frame.data[0] =
s->second_last_frame.data[0] = NULL;
return 0;
}
static int ipvideo_decode_frame(AVCodecContext *avctx,
void *data, int *data_size,
AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
IpvideoContext *s = avctx->priv_data;
AVPaletteControl *palette_control = avctx->palctrl;
/* compressed buffer needs to be large enough to at least hold an entire
* decoding map */
if (buf_size < s->decoding_map_size)
return buf_size;
s->decoding_map = buf;
s->buf = buf + s->decoding_map_size;
s->size = buf_size - s->decoding_map_size;
s->current_frame.reference = 3;
if (avctx->get_buffer(avctx, &s->current_frame)) {
av_log(avctx, AV_LOG_ERROR, " Interplay Video: get_buffer() failed\n");
return -1;
}
ipvideo_decode_opcodes(s);
if (!s->is_16bpp && palette_control->palette_changed) {
palette_control->palette_changed = 0;
s->current_frame.palette_has_changed = 1;
}
*data_size = sizeof(AVFrame);
*(AVFrame*)data = s->current_frame;
/* shuffle frames */
if (s->second_last_frame.data[0])
avctx->release_buffer(avctx, &s->second_last_frame);
s->second_last_frame = s->last_frame;
s->last_frame = s->current_frame;
s->current_frame.data[0] = NULL; /* catch any access attempts */
/* report that the buffer was completely consumed */
return buf_size;
}
static av_cold int ipvideo_decode_end(AVCodecContext *avctx)
{
IpvideoContext *s = avctx->priv_data;
/* release the last frame */
if (s->last_frame.data[0])
avctx->release_buffer(avctx, &s->last_frame);
if (s->second_last_frame.data[0])
avctx->release_buffer(avctx, &s->second_last_frame);
return 0;
}
AVCodec interplay_video_decoder = {
"interplayvideo",
AVMEDIA_TYPE_VIDEO,
CODEC_ID_INTERPLAY_VIDEO,
sizeof(IpvideoContext),
ipvideo_decode_init,
NULL,
ipvideo_decode_end,
ipvideo_decode_frame,
CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("Interplay MVE video"),
};