| /* |
| * 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 uint8_t *buf; |
| int size; |
| |
| /* scratch space */ |
| uint8_t *buffer1; |
| int buffer1_size; |
| uint8_t *buffer2; |
| int buffer2_size; |
| |
| unsigned *palettes; |
| int palettes_count; |
| int cur_palette; |
| |
| int frame_size; |
| |
| } XanContext; |
| |
| static av_cold int xan_decode_end(AVCodecContext *avctx) |
| { |
| XanContext *s = avctx->priv_data; |
| |
| av_frame_free(&s->last_frame); |
| |
| av_freep(&s->buffer1); |
| av_freep(&s->buffer2); |
| av_freep(&s->palettes); |
| |
| return 0; |
| } |
| |
| 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); |
| } |
| |
| s->last_frame = av_frame_alloc(); |
| if (!s->last_frame) { |
| xan_decode_end(avctx); |
| return AVERROR(ENOMEM); |
| } |
| |
| return 0; |
| } |
| |
| static int xan_huffman_decode(uint8_t *dest, int dest_len, |
| const uint8_t *src, int src_len) |
| { |
| uint8_t byte = *src++; |
| uint8_t ival = byte + 0x16; |
| const uint8_t * ptr = src + byte*2; |
| int ptr_len = src_len - 1 - byte*2; |
| uint8_t val = ival; |
| uint8_t *dest_end = dest + dest_len; |
| uint8_t *dest_start = dest; |
| int ret; |
| GetBitContext gb; |
| |
| if ((ret = init_get_bits8(&gb, ptr, ptr_len)) < 0) |
| return ret; |
| |
| 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 dest_len; |
| *dest++ = val; |
| val = ival; |
| } |
| } |
| |
| return dest - dest_start; |
| } |
| |
| /** |
| * unpack simple compression |
| * |
| * @param dest destination buffer of dest_len, must be padded with at least 130 bytes |
| */ |
| static void xan_unpack(uint8_t *dest, int dest_len, |
| const uint8_t *src, int src_len) |
| { |
| uint8_t opcode; |
| int size; |
| uint8_t *dest_org = dest; |
| uint8_t *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 uint8_t *pixel_buffer, int x, int y, int pixel_count) |
| { |
| int stride; |
| int line_inc; |
| int index; |
| int current_x; |
| int width = s->avctx->width; |
| uint8_t *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; |
| uint8_t *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; |
| |
| if (prev_palette_plane == palette_plane && FFABS(curframe_index - prevframe_index) < pixel_count) { |
| avpriv_request_sample(s->avctx, "Overlapping copy"); |
| return ; |
| } |
| |
| 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; |
| uint8_t opcode; |
| uint8_t flag = 0; |
| int size = 0; |
| int motion_x, motion_y; |
| int x, y, ret; |
| |
| uint8_t *opcode_buffer = s->buffer1; |
| uint8_t *opcode_buffer_end = s->buffer1 + s->buffer1_size; |
| int opcode_buffer_size = s->buffer1_size; |
| const uint8_t *imagedata_buffer = s->buffer2; |
| |
| /* pointers to segments inside the compressed chunk */ |
| const uint8_t *huffman_segment; |
| GetByteContext size_segment; |
| GetByteContext vector_segment; |
| const uint8_t *imagedata_segment; |
| 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; |
| bytestream2_init(&size_segment, s->buf + size_offset, s->size - size_offset); |
| bytestream2_init(&vector_segment, s->buf + vector_offset, s->size - vector_offset); |
| imagedata_segment = s->buf + imagedata_offset; |
| |
| if ((ret = xan_huffman_decode(opcode_buffer, opcode_buffer_size, |
| huffman_segment, s->size - huffman_offset)) < 0) |
| return AVERROR_INVALIDDATA; |
| opcode_buffer_end = opcode_buffer + ret; |
| |
| 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 (bytestream2_get_bytes_left(&size_segment) < 1) { |
| av_log(s->avctx, AV_LOG_ERROR, "size_segment overread\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| size = bytestream2_get_byte(&size_segment); |
| break; |
| |
| case 10: |
| case 20: |
| if (bytestream2_get_bytes_left(&size_segment) < 2) { |
| av_log(s->avctx, AV_LOG_ERROR, "size_segment overread\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| size = bytestream2_get_be16(&size_segment); |
| break; |
| |
| case 11: |
| case 21: |
| if (bytestream2_get_bytes_left(&size_segment) < 3) { |
| av_log(s->avctx, AV_LOG_ERROR, "size_segment overread\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| size = bytestream2_get_be24(&size_segment); |
| 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 { |
| uint8_t vector; |
| if (bytestream2_get_bytes_left(&vector_segment) <= 0) { |
| av_log(s->avctx, AV_LOG_ERROR, "vector_segment overread\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| /* run-based motion compensation from last frame */ |
| vector = bytestream2_get_byte(&vector_segment); |
| motion_x = sign_extend(vector >> 4, 4); |
| motion_y = sign_extend(vector & 0xF, 4); |
| |
| /* 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_array(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; |
| } |
| |
| AVCodec ff_xan_wc3_decoder = { |
| .name = "xan_wc3", |
| .long_name = NULL_IF_CONFIG_SMALL("Wing Commander III / Xan"), |
| .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 = AV_CODEC_CAP_DR1, |
| }; |
