*/
/**
- * @file libavcodec/xan.c
+ * @file
* Xan video decoder for Wing Commander III computer game
* by Mario Brito (mbrito@student.dei.uc.pt)
* and Mike Melanson (melanson@pcisys.net)
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
-#include <unistd.h>
#include "libavutil/intreadwrite.h"
#include "avcodec.h"
+#include "bytestream.h"
+#define ALT_BITSTREAM_READER_LE
+#include "get_bits.h"
// for av_memcpy_backptr
#include "libavutil/lzo.h"
avctx->pix_fmt = PIX_FMT_PAL8;
- if(avcodec_check_dimensions(avctx, avctx->width, avctx->height))
- return -1;
-
s->buffer1_size = avctx->width * avctx->height;
s->buffer1 = av_malloc(s->buffer1_size);
+ if (!s->buffer1)
+ return -1;
s->buffer2_size = avctx->width * avctx->height;
s->buffer2 = av_malloc(s->buffer2_size + 130);
- if (!s->buffer1 || !s->buffer2)
+ if (!s->buffer2) {
+ av_freep(&s->buffer1);
return -1;
+ }
return 0;
}
unsigned char ival = byte + 0x16;
const unsigned char * ptr = src + byte*2;
unsigned char val = ival;
- int counter = 0;
unsigned char *dest_end = dest + dest_len;
+ GetBitContext gb;
- unsigned char bits = *ptr++;
+ init_get_bits(&gb, ptr, 0); // FIXME: no src size available
while ( val != 0x16 ) {
- if ( (1 << counter) & bits )
- val = src[byte + val - 0x17];
- else
- val = src[val - 0x17];
+ val = src[val - 0x17 + get_bits1(&gb) * byte];
if ( val < 0x16 ) {
- if (dest + 1 > dest_end)
+ if (dest >= dest_end)
return 0;
*dest++ = val;
val = ival;
}
-
- if (counter++ == 7) {
- counter = 0;
- bits = *ptr++;
- }
}
return 0;
{
unsigned char opcode;
int size;
- int offset;
- int byte1, byte2, byte3;
unsigned char *dest_end = dest + dest_len;
while (dest < dest_end) {
opcode = *src++;
if (opcode < 0xe0) {
- int size2, back;
- if ( (opcode & 0x80) == 0 ) {
-
- offset = *src++;
-
- size = opcode & 3;
+ int size2, back;
+ if ( (opcode & 0x80) == 0 ) {
- size2 = ((opcode & 0x1c) >> 2) + 3;
- back = ((opcode & 0x60) << 3) + offset + 1;
+ size = opcode & 3;
- } else if ( (opcode & 0x40) == 0 ) {
+ back = ((opcode & 0x60) << 3) + *src++ + 1;
+ size2 = ((opcode & 0x1c) >> 2) + 3;
- byte1 = *src++;
- byte2 = *src++;
+ } else if ( (opcode & 0x40) == 0 ) {
- size = byte1 >> 6;
+ size = *src >> 6;
- size2 = (opcode & 0x3f) + 4;
- back = ((byte1 & 0x3f) << 8) + byte2 + 1;
-
- } else {
+ back = (bytestream_get_be16(&src) & 0x3fff) + 1;
+ size2 = (opcode & 0x3f) + 4;
- byte1 = *src++;
- byte2 = *src++;
- byte3 = *src++;
+ } else {
- size = opcode & 3;
+ size = opcode & 3;
- size2 = byte3 + 5 + ((opcode & 0xc) << 6);
- back = ((opcode & 0x10) << 12) + 1 + (byte1 << 8) + byte2;
- if (dest >= dest_end || size > dest_end - dest)
- return;
+ back = ((opcode & 0x10) << 12) + bytestream_get_be16(&src) + 1;
+ size2 = ((opcode & 0x0c) << 6) + *src++ + 5;
+ if (size + size2 > dest_end - dest)
+ return;
}
memcpy(dest, src, size); dest += size; src += size;
av_memcpy_backptr(dest, back, size2);
dest += size2;
} else {
- size = ((opcode & 0x1f) << 2) + 4;
-
- if (size > 0x70)
- break;
+ int finish = opcode >= 0xfc;
+ size = finish ? opcode & 3 : ((opcode & 0x1f) << 2) + 4;
memcpy(dest, src, size); dest += size; src += size;
+ if (finish)
+ return;
}
}
-
- size = opcode & 3;
- memcpy(dest, src, size); dest += size; src += size;
}
static inline void xan_wc3_output_pixel_run(XanContext *s,
line_inc = stride - width;
index = y * stride + x;
current_x = x;
- while((pixel_count--) && (index < s->frame_size)) {
+ while(pixel_count && (index < s->frame_size)) {
+ int count = FFMIN(pixel_count, width - current_x);
+ memcpy(palette_plane + index, pixel_buffer, count);
+ pixel_count -= count;
+ index += count;
+ pixel_buffer += count;
+ current_x += count;
- /* 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;
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)) {
+ while(pixel_count && (curframe_index < s->frame_size)) {
+ int count = FFMIN3(pixel_count, width - curframe_x, width - prevframe_x);
- palette_plane[curframe_index++] =
- prev_palette_plane[prevframe_index++];
+ memcpy(palette_plane + curframe_index, prev_palette_plane + prevframe_index, count);
+ pixel_count -= count;
+ curframe_index += count;
+ prevframe_index += count;
+ curframe_x += count;
+ prevframe_x += count;
- curframe_x++;
if (curframe_x >= width) {
curframe_index += line_inc;
curframe_x = 0;
}
- prevframe_x++;
if (prevframe_x >= width) {
prevframe_index += line_inc;
prevframe_x = 0;
}
} else {
/* run-based motion compensation from last frame */
- motion_x = (*vector_segment >> 4) & 0xF;
- motion_y = *vector_segment & 0xF;
+ motion_x = sign_extend(*vector_segment >> 4, 4);
+ motion_y = sign_extend(*vector_segment & 0xF, 4);
vector_segment++;
- /* sign extension */
- if (motion_x & 0x8)
- motion_x |= 0xFFFFFFF0;
- if (motion_y & 0x8)
- motion_y |= 0xFFFFFFF0;
-
/* copy a run of pixels from the previous frame */
xan_wc3_copy_pixel_run(s, x, y, size, motion_x, motion_y);
/* coordinate accounting */
total_pixels -= size;
- while (size) {
- if (x + size >= width) {
- y++;
- size -= (width - x);
- x = 0;
- } else {
- x += size;
- size = 0;
- }
- }
+ y += (x + size) / width;
+ x = (x + size) % width;
}
}
palette_control->palette_changed = 0;
memcpy(s->current_frame.data[1], palette_control->palette,
- AVPALETTE_SIZE);
+ AVPALETTE_SIZE);
s->current_frame.palette_has_changed = 1;
s->buf = buf;
if (s->current_frame.data[0])
avctx->release_buffer(avctx, &s->current_frame);
- av_free(s->buffer1);
- av_free(s->buffer2);
+ av_freep(&s->buffer1);
+ av_freep(&s->buffer2);
return 0;
}
AVCodec xan_wc3_decoder = {
"xan_wc3",
- CODEC_TYPE_VIDEO,
+ AVMEDIA_TYPE_VIDEO,
CODEC_ID_XAN_WC3,
sizeof(XanContext),
xan_decode_init,
/*
AVCodec xan_wc4_decoder = {
"xan_wc4",
- CODEC_TYPE_VIDEO,
+ AVMEDIA_TYPE_VIDEO,
CODEC_ID_XAN_WC4,
sizeof(XanContext),
xan_decode_init,
xan_decode_end,
xan_decode_frame,
CODEC_CAP_DR1,
+ .long_name = NULL_IF_CONFIG_SMALL("Wing Commander IV / Xxan"),
};
*/
projects / ffmpeg / blobdiff