* Wing Commander/Xan Video Decoder
* Copyright (C) 2003 the ffmpeg project
*
- * This library is free software; you can redistribute it and/or
+ * 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 of the License, or (at your option) any later version.
+ * version 2.1 of the License, or (at your option) any later version.
*
- * This library is distributed in the hope that it will be useful,
+ * 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 this library; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
/**
* @file xan.c
- * Xan video decoder for Wing Commander III & IV computer games
+ * Xan video decoder for Wing Commander III computer game
* by Mario Brito (mbrito@student.dei.uc.pt)
* and Mike Melanson (melanson@pcisys.net)
- * For more information about the Xan format, visit:
- * http://www.pcisys.net/~melanson/codecs/
+ *
+ * The xan_wc3 decoder outputs PAL8 data.
*/
#include <stdio.h>
#include <string.h>
#include <unistd.h>
-#include "common.h"
#include "avcodec.h"
-#include "dsputil.h"
-
-#define PALETTE_COUNT 256
-#define PALETTE_CONTROL_SIZE ((256 * 3) + 1)
typedef struct XanContext {
AVCodecContext *avctx;
- DSPContext dsp;
AVFrame last_frame;
AVFrame current_frame;
unsigned char *buf;
int size;
- unsigned char palette[PALETTE_COUNT * 4];
-
/* scratch space */
unsigned char *buffer1;
+ int buffer1_size;
unsigned char *buffer2;
+ int buffer2_size;
-} XanContext;
-
-#define BE_16(x) ((((uint8_t*)(x))[0] << 8) | ((uint8_t*)(x))[1])
-#define LE_16(x) ((((uint8_t*)(x))[1] << 8) | ((uint8_t*)(x))[0])
-#define LE_32(x) ((((uint8_t*)(x))[3] << 24) | \
- (((uint8_t*)(x))[2] << 16) | \
- (((uint8_t*)(x))[1] << 8) | \
- ((uint8_t*)(x))[0])
-
-/* RGB -> YUV conversion stuff */
-#define SCALEFACTOR 65536
-#define CENTERSAMPLE 128
-
-#define COMPUTE_Y(r, g, b) \
- (unsigned char) \
- ((y_r_table[r] + y_g_table[g] + y_b_table[b]) / SCALEFACTOR)
-#define COMPUTE_U(r, g, b) \
- (unsigned char) \
- ((u_r_table[r] + u_g_table[g] + u_b_table[b]) / SCALEFACTOR + CENTERSAMPLE)
-#define COMPUTE_V(r, g, b) \
- (unsigned char) \
- ((v_r_table[r] + v_g_table[g] + v_b_table[b]) / SCALEFACTOR + CENTERSAMPLE)
-
-#define Y_R (SCALEFACTOR * 0.29900)
-#define Y_G (SCALEFACTOR * 0.58700)
-#define Y_B (SCALEFACTOR * 0.11400)
-
-#define U_R (SCALEFACTOR * -0.16874)
-#define U_G (SCALEFACTOR * -0.33126)
-#define U_B (SCALEFACTOR * 0.50000)
-
-#define V_R (SCALEFACTOR * 0.50000)
-#define V_G (SCALEFACTOR * -0.41869)
-#define V_B (SCALEFACTOR * -0.08131)
+ int frame_size;
-/*
- * Precalculate all of the YUV tables since it requires fewer than
- * 10 kilobytes to store them.
- */
-static int y_r_table[256];
-static int y_g_table[256];
-static int y_b_table[256];
-
-static int u_r_table[256];
-static int u_g_table[256];
-static int u_b_table[256];
-
-static int v_r_table[256];
-static int v_g_table[256];
-static int v_b_table[256];
+} XanContext;
static int xan_decode_init(AVCodecContext *avctx)
{
XanContext *s = avctx->priv_data;
- int i;
s->avctx = avctx;
+ s->frame_size = 0;
- if ((avctx->codec->id == CODEC_ID_XAN_WC3) &&
- (s->avctx->extradata_size != PALETTE_CONTROL_SIZE)) {
- printf (" WC3 Xan video: expected extradata_size of %d\n",
- PALETTE_CONTROL_SIZE);
+ if ((avctx->codec->id == CODEC_ID_XAN_WC3) &&
+ (s->avctx->palctrl == NULL)) {
+ av_log(avctx, AV_LOG_ERROR, " WC3 Xan video: palette expected.\n");
return -1;
}
- avctx->pix_fmt = PIX_FMT_YUV444P;
- avctx->has_b_frames = 0;
- dsputil_init(&s->dsp, avctx);
-
- /* initialize the RGB -> YUV tables */
- for (i = 0; i < 256; i++) {
- y_r_table[i] = Y_R * i;
- y_g_table[i] = Y_G * i;
- y_b_table[i] = Y_B * i;
-
- u_r_table[i] = U_R * i;
- u_g_table[i] = U_G * i;
- u_b_table[i] = U_B * i;
+ avctx->pix_fmt = PIX_FMT_PAL8;
- v_r_table[i] = V_R * i;
- v_g_table[i] = V_G * i;
- v_b_table[i] = V_B * i;
- }
+ if(avcodec_check_dimensions(avctx, avctx->width, avctx->height))
+ return -1;
- s->buffer1 = av_malloc(avctx->width * avctx->height * 4);
- s->buffer2 = av_malloc(avctx->width * avctx->height * 4);
+ s->buffer1_size = avctx->width * avctx->height;
+ s->buffer1 = av_malloc(s->buffer1_size);
+ s->buffer2_size = avctx->width * avctx->height;
+ s->buffer2 = av_malloc(s->buffer2_size);
if (!s->buffer1 || !s->buffer2)
return -1;
return 0;
}
-/* This function is used in lieu of memcpy(). This decoder can not use
+/* This function is used in lieu of memcpy(). This decoder cannot use
* memcpy because the memory locations often overlap and
* memcpy doesn't like that; it's not uncommon, for example, for
* dest = src+1, to turn byte A into pattern AAAAAAAA.
dest[i] = src[i];
}
-static int xan_decode_method_1(unsigned char *dest, unsigned char *src)
+static int xan_huffman_decode(unsigned char *dest, unsigned char *src,
+ int dest_len)
{
unsigned char byte = *src++;
unsigned char ival = byte + 0x16;
unsigned char * ptr = src + byte*2;
unsigned char val = ival;
int counter = 0;
+ unsigned char *dest_end = dest + dest_len;
unsigned char bits = *ptr++;
val = src[val - 0x17];
if ( val < 0x16 ) {
+ if (dest + 1 > dest_end)
+ return 0;
*dest++ = val;
val = ival;
}
return 0;
}
-static int xan_decode_method_2(unsigned char *dest, unsigned char *src)
+static void xan_unpack(unsigned char *dest, unsigned char *src, int dest_len)
{
unsigned char opcode;
int size;
int offset;
int byte1, byte2, byte3;
+ unsigned char *dest_end = dest + dest_len;
for (;;) {
opcode = *src++;
offset = *src++;
size = opcode & 3;
+ if (dest + size > dest_end)
+ return;
bytecopy(dest, src, size); dest += size; src += size;
size = ((opcode & 0x1c) >> 2) + 3;
+ if (dest + size > dest_end)
+ return;
bytecopy (dest, dest - (((opcode & 0x60) << 3) + offset + 1), size);
dest += size;
byte2 = *src++;
size = byte1 >> 6;
+ if (dest + size > dest_end)
+ return;
bytecopy (dest, src, size); dest += size; src += size;
size = (opcode & 0x3f) + 4;
+ if (dest + size > dest_end)
+ return;
bytecopy (dest, dest - (((byte1 & 0x3f) << 8) + byte2 + 1), size);
dest += size;
byte3 = *src++;
size = opcode & 3;
+ if (dest + size > dest_end)
+ return;
bytecopy (dest, src, size); dest += size; src += size;
size = byte3 + 5 + ((opcode & 0xc) << 6);
+ if (dest + size > dest_end)
+ return;
bytecopy (dest,
dest - ((((opcode & 0x10) >> 4) << 0x10) + 1 + (byte1 << 8) + byte2),
size);
if (size > 0x70)
break;
+ if (dest + size > dest_end)
+ return;
bytecopy (dest, src, size); dest += size; src += size;
}
}
size = opcode & 3;
bytecopy(dest, src, size); dest += size; src += size;
-
- return 0;
-}
-
-static void inline xan_wc3_build_palette(XanContext *s,
- unsigned char *palette_data)
-{
- int i;
- unsigned char r, g, b;
-
- /* transform the palette passed through the palette control structure
- * into the necessary internal format depending on colorspace */
-
- switch (s->avctx->pix_fmt) {
-
- case PIX_FMT_YUV444P:
- for (i = 0; i < PALETTE_COUNT; i++) {
- r = *palette_data++;
- g = *palette_data++;
- b = *palette_data++;
- s->palette[i * 4 + 0] = COMPUTE_Y(r, g, b);
- s->palette[i * 4 + 1] = COMPUTE_U(r, g, b);
- s->palette[i * 4 + 2] = COMPUTE_V(r, g, b);
- }
- break;
-
- default:
- printf (" Xan WC3: Unhandled colorspace\n");
- break;
- }
}
-static void inline xan_wc3_output_pixel_run(XanContext *s,
+static inline void xan_wc3_output_pixel_run(XanContext *s,
unsigned char *pixel_buffer, int x, int y, int pixel_count)
{
int stride;
int index;
int current_x;
int width = s->avctx->width;
- unsigned char pixel;
- unsigned char *y_plane;
- unsigned char *u_plane;
- unsigned char *v_plane;
-
- switch (s->avctx->pix_fmt) {
-
- case PIX_FMT_YUV444P:
- y_plane = s->current_frame.data[0];
- u_plane = s->current_frame.data[1];
- v_plane = s->current_frame.data[2];
- stride = s->current_frame.linesize[0];
- line_inc = stride - width;
- index = y * stride + x;
- current_x = x;
- while(pixel_count--) {
- pixel = *pixel_buffer++;
-
- y_plane[index] = s->palette[pixel * 4 + 0];
- u_plane[index] = s->palette[pixel * 4 + 1];
- v_plane[index] = s->palette[pixel * 4 + 2];
-
- index++;
- current_x++;
- if (current_x >= width) {
- /* reset accounting variables */
- index += line_inc;
- current_x = 0;
- }
+ unsigned char *palette_plane;
+
+ palette_plane = s->current_frame.data[0];
+ stride = s->current_frame.linesize[0];
+ line_inc = stride - width;
+ index = y * stride + x;
+ current_x = x;
+ while((pixel_count--) && (index < s->frame_size)) {
+
+ /* don't do a memcpy() here; keyframes generally copy an entire
+ * frame of data and the stride needs to be accounted for */
+ palette_plane[index++] = *pixel_buffer++;
+
+ current_x++;
+ if (current_x >= width) {
+ index += line_inc;
+ current_x = 0;
}
- break;
-
- default:
- printf (" Xan WC3: Unhandled colorspace\n");
- break;
}
}
-static void inline xan_wc3_copy_pixel_run(XanContext *s,
+static inline void xan_wc3_copy_pixel_run(XanContext *s,
int x, int y, int pixel_count, int motion_x, int motion_y)
{
int stride;
int curframe_index, prevframe_index;
int curframe_x, prevframe_x;
int width = s->avctx->width;
- unsigned char *y_plane, *u_plane, *v_plane;
- unsigned char *prev_y_plane, *prev_u_plane, *prev_v_plane;
-
- switch (s->avctx->pix_fmt) {
-
- case PIX_FMT_YUV444P:
- y_plane = s->current_frame.data[0];
- u_plane = s->current_frame.data[1];
- v_plane = s->current_frame.data[2];
- prev_y_plane = s->last_frame.data[0];
- prev_u_plane = s->last_frame.data[1];
- prev_v_plane = s->last_frame.data[2];
- stride = s->current_frame.linesize[0];
- line_inc = stride - width;
- curframe_index = y * stride + x;
- curframe_x = x;
- prevframe_index = (y + motion_x) * stride + x + motion_x;
- prevframe_x = x + motion_x;
- while(pixel_count--) {
-
- y_plane[curframe_index] = prev_y_plane[prevframe_index];
- u_plane[curframe_index] = prev_u_plane[prevframe_index];
- v_plane[curframe_index] = prev_v_plane[prevframe_index];
-
- curframe_index++;
- curframe_x++;
- if (curframe_x >= width) {
- /* reset accounting variables */
- curframe_index += line_inc;
- curframe_x = 0;
- }
-
- prevframe_index++;
- prevframe_x++;
- if (prevframe_x >= width) {
- /* reset accounting variables */
- prevframe_index += line_inc;
- prevframe_x = 0;
- }
+ unsigned char *palette_plane, *prev_palette_plane;
+
+ palette_plane = s->current_frame.data[0];
+ prev_palette_plane = s->last_frame.data[0];
+ stride = s->current_frame.linesize[0];
+ line_inc = stride - width;
+ curframe_index = y * stride + x;
+ curframe_x = x;
+ prevframe_index = (y + motion_y) * stride + x + motion_x;
+ prevframe_x = x + motion_x;
+ while((pixel_count--) && (curframe_index < s->frame_size)) {
+
+ palette_plane[curframe_index++] =
+ prev_palette_plane[prevframe_index++];
+
+ curframe_x++;
+ if (curframe_x >= width) {
+ curframe_index += line_inc;
+ curframe_x = 0;
}
- break;
- default:
- printf (" Xan WC3: Unhandled colorspace\n");
- break;
+ prevframe_x++;
+ if (prevframe_x >= width) {
+ prevframe_index += line_inc;
+ prevframe_x = 0;
+ }
}
}
int motion_x, motion_y;
int x, y;
- unsigned char *method1_buffer = s->buffer1;
- unsigned char *method2_buffer = s->buffer2;
+ unsigned char *opcode_buffer = s->buffer1;
+ int opcode_buffer_size = s->buffer1_size;
+ unsigned char *imagedata_buffer = s->buffer2;
+ int imagedata_buffer_size = s->buffer2_size;
/* pointers to segments inside the compressed chunk */
- unsigned char *method1_segment;
+ unsigned char *huffman_segment;
unsigned char *size_segment;
unsigned char *vector_segment;
- unsigned char *method2_segment;
+ unsigned char *imagedata_segment;
+
+ huffman_segment = s->buf + AV_RL16(&s->buf[0]);
+ size_segment = s->buf + AV_RL16(&s->buf[2]);
+ vector_segment = s->buf + AV_RL16(&s->buf[4]);
+ imagedata_segment = s->buf + AV_RL16(&s->buf[6]);
- method1_segment = s->buf + LE_16(&s->buf[0]);
- size_segment = s->buf + LE_16(&s->buf[2]);
- vector_segment = s->buf + LE_16(&s->buf[4]);
- method2_segment = s->buf + LE_16(&s->buf[6]);
+ xan_huffman_decode(opcode_buffer, huffman_segment, opcode_buffer_size);
- xan_decode_method_1(method1_buffer, method1_segment);
- if (method2_segment[0] == 2)
- xan_decode_method_2(method2_buffer, method2_segment + 1);
+ if (imagedata_segment[0] == 2)
+ xan_unpack(imagedata_buffer, &imagedata_segment[1],
+ imagedata_buffer_size);
else
- method2_buffer = method2_segment + 1;
+ imagedata_buffer = &imagedata_segment[1];
/* use the decoded data segments to build the frame */
x = y = 0;
while (total_pixels) {
- opcode = *method1_buffer++;
+ opcode = *opcode_buffer++;
size = 0;
switch (opcode) {
case 10:
case 20:
- size = BE_16(&size_segment[0]);
+ size = AV_RB16(&size_segment[0]);
size_segment += 2;
break;
case 11:
case 21:
- size = (size_segment[0] << 16) | (size_segment[1] << 8) |
- size_segment[2];
+ size = AV_RB24(size_segment);
size_segment += 3;
break;
}
/* run of (size) pixels is unchanged from last frame */
xan_wc3_copy_pixel_run(s, x, y, size, 0, 0);
} else {
- /* output a run of pixels from method2_buffer */
- xan_wc3_output_pixel_run(s, method2_buffer, x, y, size);
- method2_buffer += size;
+ /* output a run of pixels from imagedata_buffer */
+ xan_wc3_output_pixel_run(s, imagedata_buffer, x, y, size);
+ imagedata_buffer += size;
}
} else {
/* run-based motion compensation from last frame */
uint8_t *buf, int buf_size)
{
XanContext *s = avctx->priv_data;
- unsigned char *palette_control = avctx->extradata;
- int keyframe = 0;
-
- if (palette_control[0]) {
- /* load the new palette and reset the palette control */
- xan_wc3_build_palette(s, &palette_control[1]);
- palette_control[0] = 0;
- keyframe = 1;
- }
+ AVPaletteControl *palette_control = avctx->palctrl;
if (avctx->get_buffer(avctx, &s->current_frame)) {
- printf (" Interplay Video: get_buffer() failed\n");
+ av_log(s->avctx, AV_LOG_ERROR, " Xan Video: get_buffer() failed\n");
return -1;
}
+ s->current_frame.reference = 3;
+
+ if (!s->frame_size)
+ s->frame_size = s->current_frame.linesize[0] * s->avctx->height;
+
+ palette_control->palette_changed = 0;
+ memcpy(s->current_frame.data[1], palette_control->palette,
+ AVPALETTE_SIZE);
+ s->current_frame.palette_has_changed = 1;
s->buf = buf;
s->size = buf_size;
- if (avctx->codec->id == CODEC_ID_XAN_WC3) {
-// if (keyframe)
- if (1)
- xan_wc3_decode_frame(s);
- else {
- memcpy(s->current_frame.data[0], s->last_frame.data[0],
- s->current_frame.linesize[0] * avctx->height);
- memcpy(s->current_frame.data[1], s->last_frame.data[1],
- s->current_frame.linesize[1] * avctx->height);
- memcpy(s->current_frame.data[2], s->last_frame.data[2],
- s->current_frame.linesize[2] * avctx->height);
- }
- } else if (avctx->codec->id == CODEC_ID_XAN_WC4)
+ if (avctx->codec->id == CODEC_ID_XAN_WC3)
+ xan_wc3_decode_frame(s);
+ else if (avctx->codec->id == CODEC_ID_XAN_WC4)
xan_wc4_decode_frame(s);
-
+
/* release the last frame if it is allocated */
if (s->last_frame.data[0])
avctx->release_buffer(avctx, &s->last_frame);
XanContext *s = avctx->priv_data;
/* release the last frame */
- avctx->release_buffer(avctx, &s->last_frame);
+ if (s->last_frame.data[0])
+ avctx->release_buffer(avctx, &s->last_frame);
av_free(s->buffer1);
av_free(s->buffer2);