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-rw-r--r--contrib/ffmpeg/libavcodec/xan.c492
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diff --git a/contrib/ffmpeg/libavcodec/xan.c b/contrib/ffmpeg/libavcodec/xan.c
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+++ b/contrib/ffmpeg/libavcodec/xan.c
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+/*
+ * Wing Commander/Xan 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 xan.c
+ * Xan video decoder for Wing Commander III computer game
+ * by Mario Brito (mbrito@student.dei.uc.pt)
+ * and Mike Melanson (melanson@pcisys.net)
+ *
+ * The xan_wc3 decoder outputs PAL8 data.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "common.h"
+#include "avcodec.h"
+
+typedef struct XanContext {
+
+ AVCodecContext *avctx;
+ AVFrame last_frame;
+ AVFrame current_frame;
+
+ unsigned char *buf;
+ int size;
+
+ /* scratch space */
+ unsigned char *buffer1;
+ int buffer1_size;
+ unsigned char *buffer2;
+ int buffer2_size;
+
+ int frame_size;
+
+} XanContext;
+
+static int xan_decode_init(AVCodecContext *avctx)
+{
+ XanContext *s = avctx->priv_data;
+
+ s->avctx = avctx;
+ s->frame_size = 0;
+
+ 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_PAL8;
+ avctx->has_b_frames = 0;
+
+ 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);
+ 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
+ * 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.
+ * This was originally repz movsb in Intel x86 ASM. */
+static inline void bytecopy(unsigned char *dest, unsigned char *src, int count)
+{
+ int i;
+
+ for (i = 0; i < count; i++)
+ dest[i] = src[i];
+}
+
+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++;
+
+ while ( val != 0x16 ) {
+ if ( (1 << counter) & bits )
+ val = src[byte + val - 0x17];
+ else
+ val = src[val - 0x17];
+
+ if ( val < 0x16 ) {
+ if (dest + 1 > dest_end)
+ return 0;
+ *dest++ = val;
+ val = ival;
+ }
+
+ if (counter++ == 7) {
+ counter = 0;
+ bits = *ptr++;
+ }
+ }
+
+ return 0;
+}
+
+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++;
+
+ if ( (opcode & 0x80) == 0 ) {
+
+ 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;
+
+ } else if ( (opcode & 0x40) == 0 ) {
+
+ byte1 = *src++;
+ 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;
+
+ } else if ( (opcode & 0x20) == 0 ) {
+
+ byte1 = *src++;
+ byte2 = *src++;
+ 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);
+ dest += size;
+ } else {
+ size = ((opcode & 0x1f) << 2) + 4;
+
+ 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;
+}
+
+static void inline xan_wc3_output_pixel_run(XanContext *s,
+ unsigned char *pixel_buffer, int x, int y, int pixel_count)
+{
+ int stride;
+ int line_inc;
+ int index;
+ int current_x;
+ int width = s->avctx->width;
+ 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;
+ }
+ }
+}
+
+static void inline xan_wc3_copy_pixel_run(XanContext *s,
+ int x, int y, int pixel_count, int motion_x, int motion_y)
+{
+ int stride;
+ int line_inc;
+ int curframe_index, prevframe_index;
+ int curframe_x, prevframe_x;
+ int width = s->avctx->width;
+ 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;
+ }
+
+ prevframe_x++;
+ if (prevframe_x >= width) {
+ prevframe_index += line_inc;
+ prevframe_x = 0;
+ }
+ }
+}
+
+static void xan_wc3_decode_frame(XanContext *s) {
+
+ int width = s->avctx->width;
+ int height = s->avctx->height;
+ int total_pixels = width * height;
+ unsigned char opcode;
+ unsigned char flag = 0;
+ int size = 0;
+ int motion_x, motion_y;
+ int x, y;
+
+ 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 *huffman_segment;
+ unsigned char *size_segment;
+ unsigned char *vector_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]);
+
+ xan_huffman_decode(opcode_buffer, huffman_segment, opcode_buffer_size);
+
+ if (imagedata_segment[0] == 2)
+ xan_unpack(imagedata_buffer, &imagedata_segment[1],
+ imagedata_buffer_size);
+ else
+ imagedata_buffer = &imagedata_segment[1];
+
+ /* use the decoded data segments to build the frame */
+ x = y = 0;
+ while (total_pixels) {
+
+ opcode = *opcode_buffer++;
+ size = 0;
+
+ switch (opcode) {
+
+ case 0:
+ flag ^= 1;
+ continue;
+
+ case 1:
+ case 2:
+ case 3:
+ case 4:
+ case 5:
+ case 6:
+ case 7:
+ case 8:
+ size = opcode;
+ break;
+
+ case 12:
+ case 13:
+ case 14:
+ case 15:
+ case 16:
+ case 17:
+ case 18:
+ size += (opcode - 10);
+ break;
+
+ case 9:
+ case 19:
+ size = *size_segment++;
+ break;
+
+ case 10:
+ case 20:
+ 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_segment += 3;
+ break;
+ }
+
+ if (opcode < 12) {
+ flag ^= 1;
+ if (flag) {
+ /* 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 imagedata_buffer */
+ xan_wc3_output_pixel_run(s, imagedata_buffer, x, y, size);
+ imagedata_buffer += size;
+ }
+ } else {
+ /* run-based motion compensation from last frame */
+ motion_x = (*vector_segment >> 4) & 0xF;
+ motion_y = *vector_segment & 0xF;
+ 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);
+
+ flag = 0;
+ }
+
+ /* coordinate accounting */
+ total_pixels -= size;
+ while (size) {
+ if (x + size >= width) {
+ y++;
+ size -= (width - x);
+ x = 0;
+ } else {
+ x += size;
+ size = 0;
+ }
+ }
+ }
+}
+
+static void xan_wc4_decode_frame(XanContext *s) {
+}
+
+static int xan_decode_frame(AVCodecContext *avctx,
+ void *data, int *data_size,
+ uint8_t *buf, int buf_size)
+{
+ XanContext *s = avctx->priv_data;
+ AVPaletteControl *palette_control = avctx->palctrl;
+
+ if (avctx->get_buffer(avctx, &s->current_frame)) {
+ 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)
+ 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);
+
+ /* shuffle frames */
+ s->last_frame = s->current_frame;
+
+ *data_size = sizeof(AVFrame);
+ *(AVFrame*)data = s->current_frame;
+
+ /* always report that the buffer was completely consumed */
+ return buf_size;
+}
+
+static int xan_decode_end(AVCodecContext *avctx)
+{
+ XanContext *s = avctx->priv_data;
+
+ /* release the last frame */
+ if (s->last_frame.data[0])
+ avctx->release_buffer(avctx, &s->last_frame);
+
+ av_free(s->buffer1);
+ av_free(s->buffer2);
+
+ return 0;
+}
+
+AVCodec xan_wc3_decoder = {
+ "xan_wc3",
+ CODEC_TYPE_VIDEO,
+ CODEC_ID_XAN_WC3,
+ sizeof(XanContext),
+ xan_decode_init,
+ NULL,
+ xan_decode_end,
+ xan_decode_frame,
+ CODEC_CAP_DR1,
+};
+
+/*
+AVCodec xan_wc4_decoder = {
+ "xan_wc4",
+ CODEC_TYPE_VIDEO,
+ CODEC_ID_XAN_WC4,
+ sizeof(XanContext),
+ xan_decode_init,
+ NULL,
+ xan_decode_end,
+ xan_decode_frame,
+ CODEC_CAP_DR1,
+};
+*/
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