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Diffstat (limited to 'ffmpeg1/libavcodec/xan.c')
-rw-r--r--ffmpeg1/libavcodec/xan.c638
1 files changed, 0 insertions, 638 deletions
diff --git a/ffmpeg1/libavcodec/xan.c b/ffmpeg1/libavcodec/xan.c
deleted file mode 100644
index 2ee2291..0000000
--- a/ffmpeg1/libavcodec/xan.c
+++ /dev/null
@@ -1,638 +0,0 @@
-/*
- * 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 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 "libavutil/intreadwrite.h"
-#include "libavutil/mem.h"
-#include "avcodec.h"
-#include "bytestream.h"
-#define BITSTREAM_READER_LE
-#include "get_bits.h"
-#include "internal.h"
-
-#define RUNTIME_GAMMA 0
-
-#define VGA__TAG MKTAG('V', 'G', 'A', ' ')
-#define PALT_TAG MKTAG('P', 'A', 'L', 'T')
-#define SHOT_TAG MKTAG('S', 'H', 'O', 'T')
-#define PALETTE_COUNT 256
-#define PALETTE_SIZE (PALETTE_COUNT * 3)
-#define PALETTES_MAX 256
-
-typedef struct XanContext {
-
- AVCodecContext *avctx;
- AVFrame last_frame;
-
- const unsigned char *buf;
- int size;
-
- /* scratch space */
- unsigned char *buffer1;
- int buffer1_size;
- unsigned char *buffer2;
- int buffer2_size;
-
- unsigned *palettes;
- int palettes_count;
- int cur_palette;
-
- int frame_size;
-
-} XanContext;
-
-static av_cold int xan_decode_init(AVCodecContext *avctx)
-{
- XanContext *s = avctx->priv_data;
-
- s->avctx = avctx;
- s->frame_size = 0;
-
- avctx->pix_fmt = AV_PIX_FMT_PAL8;
-
- s->buffer1_size = avctx->width * avctx->height;
- s->buffer1 = av_malloc(s->buffer1_size);
- if (!s->buffer1)
- return AVERROR(ENOMEM);
- s->buffer2_size = avctx->width * avctx->height;
- s->buffer2 = av_malloc(s->buffer2_size + 130);
- if (!s->buffer2) {
- av_freep(&s->buffer1);
- return AVERROR(ENOMEM);
- }
- avcodec_get_frame_defaults(&s->last_frame);
-
- return 0;
-}
-
-static int xan_huffman_decode(unsigned char *dest, int dest_len,
- const unsigned char *src, int src_len)
-{
- unsigned char byte = *src++;
- unsigned char ival = byte + 0x16;
- const unsigned char * ptr = src + byte*2;
- int ptr_len = src_len - 1 - byte*2;
- unsigned char val = ival;
- unsigned char *dest_end = dest + dest_len;
- GetBitContext gb;
-
- if (ptr_len < 0)
- return AVERROR_INVALIDDATA;
-
- init_get_bits(&gb, ptr, ptr_len * 8);
-
- while (val != 0x16) {
- unsigned idx = val - 0x17 + get_bits1(&gb) * byte;
- if (idx >= 2 * byte)
- return AVERROR_INVALIDDATA;
- val = src[idx];
-
- if (val < 0x16) {
- if (dest >= dest_end)
- return 0;
- *dest++ = val;
- val = ival;
- }
- }
-
- return 0;
-}
-
-/**
- * unpack simple compression
- *
- * @param dest destination buffer of dest_len, must be padded with at least 130 bytes
- */
-static void xan_unpack(unsigned char *dest, int dest_len,
- const unsigned char *src, int src_len)
-{
- unsigned char opcode;
- int size;
- unsigned char *dest_org = dest;
- unsigned char *dest_end = dest + dest_len;
- GetByteContext ctx;
-
- bytestream2_init(&ctx, src, src_len);
- while (dest < dest_end && bytestream2_get_bytes_left(&ctx)) {
- opcode = bytestream2_get_byte(&ctx);
-
- if (opcode < 0xe0) {
- int size2, back;
- if ((opcode & 0x80) == 0) {
- size = opcode & 3;
-
- back = ((opcode & 0x60) << 3) + bytestream2_get_byte(&ctx) + 1;
- size2 = ((opcode & 0x1c) >> 2) + 3;
- } else if ((opcode & 0x40) == 0) {
- size = bytestream2_peek_byte(&ctx) >> 6;
-
- back = (bytestream2_get_be16(&ctx) & 0x3fff) + 1;
- size2 = (opcode & 0x3f) + 4;
- } else {
- size = opcode & 3;
-
- back = ((opcode & 0x10) << 12) + bytestream2_get_be16(&ctx) + 1;
- size2 = ((opcode & 0x0c) << 6) + bytestream2_get_byte(&ctx) + 5;
- }
-
- if (dest_end - dest < size + size2 ||
- dest + size - dest_org < back ||
- bytestream2_get_bytes_left(&ctx) < size)
- return;
- bytestream2_get_buffer(&ctx, dest, size);
- dest += size;
- av_memcpy_backptr(dest, back, size2);
- dest += size2;
- } else {
- int finish = opcode >= 0xfc;
- size = finish ? opcode & 3 : ((opcode & 0x1f) << 2) + 4;
-
- if (dest_end - dest < size || bytestream2_get_bytes_left(&ctx) < size)
- return;
- bytestream2_get_buffer(&ctx, dest, size);
- dest += size;
- if (finish)
- return;
- }
- }
-}
-
-static inline void xan_wc3_output_pixel_run(XanContext *s, AVFrame *frame,
- const 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 = frame->data[0];
- stride = frame->linesize[0];
- line_inc = stride - width;
- index = y * stride + x;
- current_x = x;
- 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;
-
- if (current_x >= width) {
- index += line_inc;
- current_x = 0;
- }
- }
-}
-
-static inline void xan_wc3_copy_pixel_run(XanContext *s, AVFrame *frame,
- 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;
-
- if (y + motion_y < 0 || y + motion_y >= s->avctx->height ||
- x + motion_x < 0 || x + motion_x >= s->avctx->width)
- return;
-
- palette_plane = frame->data[0];
- prev_palette_plane = s->last_frame.data[0];
- if (!prev_palette_plane)
- prev_palette_plane = palette_plane;
- stride = 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 &&
- prevframe_index < s->frame_size) {
- int count = FFMIN3(pixel_count, width - curframe_x,
- width - prevframe_x);
-
- 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;
-
- if (curframe_x >= width) {
- curframe_index += line_inc;
- curframe_x = 0;
- }
-
- if (prevframe_x >= width) {
- prevframe_index += line_inc;
- prevframe_x = 0;
- }
- }
-}
-
-static int xan_wc3_decode_frame(XanContext *s, AVFrame *frame)
-{
-
- 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;
- unsigned char *opcode_buffer_end = s->buffer1 + s->buffer1_size;
- int opcode_buffer_size = s->buffer1_size;
- const unsigned char *imagedata_buffer = s->buffer2;
-
- /* pointers to segments inside the compressed chunk */
- const unsigned char *huffman_segment;
- const unsigned char *size_segment;
- const unsigned char *vector_segment;
- const unsigned char *imagedata_segment;
- const unsigned char *buf_end = s->buf + s->size;
- int huffman_offset, size_offset, vector_offset, imagedata_offset,
- imagedata_size;
-
- if (s->size < 8)
- return AVERROR_INVALIDDATA;
-
- huffman_offset = AV_RL16(&s->buf[0]);
- size_offset = AV_RL16(&s->buf[2]);
- vector_offset = AV_RL16(&s->buf[4]);
- imagedata_offset = AV_RL16(&s->buf[6]);
-
- if (huffman_offset >= s->size ||
- size_offset >= s->size ||
- vector_offset >= s->size ||
- imagedata_offset >= s->size)
- return AVERROR_INVALIDDATA;
-
- huffman_segment = s->buf + huffman_offset;
- size_segment = s->buf + size_offset;
- vector_segment = s->buf + vector_offset;
- imagedata_segment = s->buf + imagedata_offset;
-
- if (xan_huffman_decode(opcode_buffer, opcode_buffer_size,
- huffman_segment, s->size - huffman_offset) < 0)
- return AVERROR_INVALIDDATA;
-
- if (imagedata_segment[0] == 2) {
- xan_unpack(s->buffer2, s->buffer2_size,
- &imagedata_segment[1], s->size - imagedata_offset - 1);
- imagedata_size = s->buffer2_size;
- } else {
- imagedata_size = s->size - imagedata_offset - 1;
- imagedata_buffer = &imagedata_segment[1];
- }
-
- /* use the decoded data segments to build the frame */
- x = y = 0;
- while (total_pixels && opcode_buffer < opcode_buffer_end) {
-
- 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:
- if (buf_end - size_segment < 1) {
- av_log(s->avctx, AV_LOG_ERROR, "size_segment overread\n");
- return AVERROR_INVALIDDATA;
- }
- size = *size_segment++;
- break;
-
- case 10:
- case 20:
- if (buf_end - size_segment < 2) {
- av_log(s->avctx, AV_LOG_ERROR, "size_segment overread\n");
- return AVERROR_INVALIDDATA;
- }
- size = AV_RB16(&size_segment[0]);
- size_segment += 2;
- break;
-
- case 11:
- case 21:
- if (buf_end - size_segment < 3) {
- av_log(s->avctx, AV_LOG_ERROR, "size_segment overread\n");
- return AVERROR_INVALIDDATA;
- }
- size = AV_RB24(size_segment);
- size_segment += 3;
- break;
- }
-
- if (size > total_pixels)
- break;
-
- if (opcode < 12) {
- flag ^= 1;
- if (flag) {
- /* run of (size) pixels is unchanged from last frame */
- xan_wc3_copy_pixel_run(s, frame, x, y, size, 0, 0);
- } else {
- /* output a run of pixels from imagedata_buffer */
- if (imagedata_size < size)
- break;
- xan_wc3_output_pixel_run(s, frame, imagedata_buffer, x, y, size);
- imagedata_buffer += size;
- imagedata_size -= size;
- }
- } else {
- if (vector_segment >= buf_end) {
- av_log(s->avctx, AV_LOG_ERROR, "vector_segment overread\n");
- return AVERROR_INVALIDDATA;
- }
- /* run-based motion compensation from last frame */
- motion_x = sign_extend(*vector_segment >> 4, 4);
- motion_y = sign_extend(*vector_segment & 0xF, 4);
- vector_segment++;
-
- /* copy a run of pixels from the previous frame */
- xan_wc3_copy_pixel_run(s, frame, x, y, size, motion_x, motion_y);
-
- flag = 0;
- }
-
- /* coordinate accounting */
- total_pixels -= size;
- y += (x + size) / width;
- x = (x + size) % width;
- }
- return 0;
-}
-
-#if RUNTIME_GAMMA
-static inline unsigned mul(unsigned a, unsigned b)
-{
- return (a * b) >> 16;
-}
-
-static inline unsigned pow4(unsigned a)
-{
- unsigned square = mul(a, a);
- return mul(square, square);
-}
-
-static inline unsigned pow5(unsigned a)
-{
- return mul(pow4(a), a);
-}
-
-static uint8_t gamma_corr(uint8_t in) {
- unsigned lo, hi = 0xff40, target;
- int i = 15;
- in = (in << 2) | (in >> 6);
- /* equivalent float code:
- if (in >= 252)
- return 253;
- return round(pow(in / 256.0, 0.8) * 256);
- */
- lo = target = in << 8;
- do {
- unsigned mid = (lo + hi) >> 1;
- unsigned pow = pow5(mid);
- if (pow > target) hi = mid;
- else lo = mid;
- } while (--i);
- return (pow4((lo + hi) >> 1) + 0x80) >> 8;
-}
-#else
-/**
- * This is a gamma correction that xan3 applies to all palette entries.
- *
- * There is a peculiarity, namely that the values are clamped to 253 -
- * it seems likely that this table was calculated by a buggy fixed-point
- * implementation, the one above under RUNTIME_GAMMA behaves like this for
- * example.
- * The exponent value of 0.8 can be explained by this as well, since 0.8 = 4/5
- * and thus pow(x, 0.8) is still easy to calculate.
- * Also, the input values are first rotated to the left by 2.
- */
-static const uint8_t gamma_lookup[256] = {
- 0x00, 0x09, 0x10, 0x16, 0x1C, 0x21, 0x27, 0x2C,
- 0x31, 0x35, 0x3A, 0x3F, 0x43, 0x48, 0x4C, 0x50,
- 0x54, 0x59, 0x5D, 0x61, 0x65, 0x69, 0x6D, 0x71,
- 0x75, 0x79, 0x7D, 0x80, 0x84, 0x88, 0x8C, 0x8F,
- 0x93, 0x97, 0x9A, 0x9E, 0xA2, 0xA5, 0xA9, 0xAC,
- 0xB0, 0xB3, 0xB7, 0xBA, 0xBE, 0xC1, 0xC5, 0xC8,
- 0xCB, 0xCF, 0xD2, 0xD5, 0xD9, 0xDC, 0xDF, 0xE3,
- 0xE6, 0xE9, 0xED, 0xF0, 0xF3, 0xF6, 0xFA, 0xFD,
- 0x03, 0x0B, 0x12, 0x18, 0x1D, 0x23, 0x28, 0x2D,
- 0x32, 0x36, 0x3B, 0x40, 0x44, 0x49, 0x4D, 0x51,
- 0x56, 0x5A, 0x5E, 0x62, 0x66, 0x6A, 0x6E, 0x72,
- 0x76, 0x7A, 0x7D, 0x81, 0x85, 0x89, 0x8D, 0x90,
- 0x94, 0x98, 0x9B, 0x9F, 0xA2, 0xA6, 0xAA, 0xAD,
- 0xB1, 0xB4, 0xB8, 0xBB, 0xBF, 0xC2, 0xC5, 0xC9,
- 0xCC, 0xD0, 0xD3, 0xD6, 0xDA, 0xDD, 0xE0, 0xE4,
- 0xE7, 0xEA, 0xED, 0xF1, 0xF4, 0xF7, 0xFA, 0xFD,
- 0x05, 0x0D, 0x13, 0x19, 0x1F, 0x24, 0x29, 0x2E,
- 0x33, 0x38, 0x3C, 0x41, 0x45, 0x4A, 0x4E, 0x52,
- 0x57, 0x5B, 0x5F, 0x63, 0x67, 0x6B, 0x6F, 0x73,
- 0x77, 0x7B, 0x7E, 0x82, 0x86, 0x8A, 0x8D, 0x91,
- 0x95, 0x99, 0x9C, 0xA0, 0xA3, 0xA7, 0xAA, 0xAE,
- 0xB2, 0xB5, 0xB9, 0xBC, 0xBF, 0xC3, 0xC6, 0xCA,
- 0xCD, 0xD0, 0xD4, 0xD7, 0xDA, 0xDE, 0xE1, 0xE4,
- 0xE8, 0xEB, 0xEE, 0xF1, 0xF5, 0xF8, 0xFB, 0xFD,
- 0x07, 0x0E, 0x15, 0x1A, 0x20, 0x25, 0x2A, 0x2F,
- 0x34, 0x39, 0x3D, 0x42, 0x46, 0x4B, 0x4F, 0x53,
- 0x58, 0x5C, 0x60, 0x64, 0x68, 0x6C, 0x70, 0x74,
- 0x78, 0x7C, 0x7F, 0x83, 0x87, 0x8B, 0x8E, 0x92,
- 0x96, 0x99, 0x9D, 0xA1, 0xA4, 0xA8, 0xAB, 0xAF,
- 0xB2, 0xB6, 0xB9, 0xBD, 0xC0, 0xC4, 0xC7, 0xCB,
- 0xCE, 0xD1, 0xD5, 0xD8, 0xDB, 0xDF, 0xE2, 0xE5,
- 0xE9, 0xEC, 0xEF, 0xF2, 0xF6, 0xF9, 0xFC, 0xFD
-};
-#endif
-
-static int xan_decode_frame(AVCodecContext *avctx,
- void *data, int *got_frame,
- AVPacket *avpkt)
-{
- AVFrame *frame = data;
- const uint8_t *buf = avpkt->data;
- int ret, buf_size = avpkt->size;
- XanContext *s = avctx->priv_data;
- GetByteContext ctx;
- int tag = 0;
-
- bytestream2_init(&ctx, buf, buf_size);
- while (bytestream2_get_bytes_left(&ctx) > 8 && tag != VGA__TAG) {
- unsigned *tmpptr;
- uint32_t new_pal;
- int size;
- int i;
- tag = bytestream2_get_le32(&ctx);
- size = bytestream2_get_be32(&ctx);
- if(size < 0) {
- av_log(avctx, AV_LOG_ERROR, "Invalid tag size %d\n", size);
- return AVERROR_INVALIDDATA;
- }
- size = FFMIN(size, bytestream2_get_bytes_left(&ctx));
- switch (tag) {
- case PALT_TAG:
- if (size < PALETTE_SIZE)
- return AVERROR_INVALIDDATA;
- if (s->palettes_count >= PALETTES_MAX)
- return AVERROR_INVALIDDATA;
- tmpptr = av_realloc(s->palettes,
- (s->palettes_count + 1) * AVPALETTE_SIZE);
- if (!tmpptr)
- return AVERROR(ENOMEM);
- s->palettes = tmpptr;
- tmpptr += s->palettes_count * AVPALETTE_COUNT;
- for (i = 0; i < PALETTE_COUNT; i++) {
-#if RUNTIME_GAMMA
- int r = gamma_corr(bytestream2_get_byteu(&ctx));
- int g = gamma_corr(bytestream2_get_byteu(&ctx));
- int b = gamma_corr(bytestream2_get_byteu(&ctx));
-#else
- int r = gamma_lookup[bytestream2_get_byteu(&ctx)];
- int g = gamma_lookup[bytestream2_get_byteu(&ctx)];
- int b = gamma_lookup[bytestream2_get_byteu(&ctx)];
-#endif
- *tmpptr++ = (0xFFU << 24) | (r << 16) | (g << 8) | b;
- }
- s->palettes_count++;
- break;
- case SHOT_TAG:
- if (size < 4)
- return AVERROR_INVALIDDATA;
- new_pal = bytestream2_get_le32(&ctx);
- if (new_pal < s->palettes_count) {
- s->cur_palette = new_pal;
- } else
- av_log(avctx, AV_LOG_ERROR, "Invalid palette selected\n");
- break;
- case VGA__TAG:
- break;
- default:
- bytestream2_skip(&ctx, size);
- break;
- }
- }
- buf_size = bytestream2_get_bytes_left(&ctx);
-
- if (s->palettes_count <= 0) {
- av_log(s->avctx, AV_LOG_ERROR, "No palette found\n");
- return AVERROR_INVALIDDATA;
- }
-
- if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
- return ret;
-
- if (!s->frame_size)
- s->frame_size = frame->linesize[0] * s->avctx->height;
-
- memcpy(frame->data[1],
- s->palettes + s->cur_palette * AVPALETTE_COUNT, AVPALETTE_SIZE);
-
- s->buf = ctx.buffer;
- s->size = buf_size;
-
- if (xan_wc3_decode_frame(s, frame) < 0)
- return AVERROR_INVALIDDATA;
-
- av_frame_unref(&s->last_frame);
- if ((ret = av_frame_ref(&s->last_frame, frame)) < 0)
- return ret;
-
- *got_frame = 1;
-
- /* always report that the buffer was completely consumed */
- return buf_size;
-}
-
-static av_cold int xan_decode_end(AVCodecContext *avctx)
-{
- XanContext *s = avctx->priv_data;
-
- av_frame_unref(&s->last_frame);
-
- av_freep(&s->buffer1);
- av_freep(&s->buffer2);
- av_freep(&s->palettes);
-
- return 0;
-}
-
-AVCodec ff_xan_wc3_decoder = {
- .name = "xan_wc3",
- .type = AVMEDIA_TYPE_VIDEO,
- .id = AV_CODEC_ID_XAN_WC3,
- .priv_data_size = sizeof(XanContext),
- .init = xan_decode_init,
- .close = xan_decode_end,
- .decode = xan_decode_frame,
- .capabilities = CODEC_CAP_DR1,
- .long_name = NULL_IF_CONFIG_SMALL("Wing Commander III / Xan"),
-};
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