X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fxan.c;h=876a9a5558bccf6071cd5cc93d3daf4e5b26a268;hb=20d33ee8b1d2cf5ba4b4d4a81db0ff7b4a125dd3;hp=27fc16488a8d31e070e2e0bb7107f828b25b254c;hpb=9f5bd89506c140c75a0064cdfb92dcbd889efcd4;p=ffmpeg diff --git a/libavcodec/xan.c b/libavcodec/xan.c index 27fc16488a8..876a9a5558b 100644 --- a/libavcodec/xan.c +++ b/libavcodec/xan.c @@ -2,25 +2,25 @@ * Wing Commander/Xan Video Decoder * Copyright (C) 2003 the ffmpeg project * - * This file is part of FFmpeg. + * This file is part of Libav. * - * FFmpeg is free software; you can redistribute it and/or + * Libav 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, + * Libav 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 + * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** - * @file 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) @@ -31,9 +31,23 @@ #include #include #include -#include +#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" + +#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 { @@ -50,51 +64,37 @@ typedef struct XanContext { unsigned char *buffer2; int buffer2_size; + unsigned *palettes; + int palettes_count; + int cur_palette; + int frame_size; } XanContext; -static int xan_decode_init(AVCodecContext *avctx) +static av_cold 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; - 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 AVERROR(ENOMEM); s->buffer2_size = avctx->width * avctx->height; - s->buffer2 = av_malloc(s->buffer2_size); - if (!s->buffer1 || !s->buffer2) - return -1; + s->buffer2 = av_malloc(s->buffer2_size + 130); + if (!s->buffer2) { + av_freep(&s->buffer1); + return AVERROR(ENOMEM); + } return 0; } -/* 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. - * This was originally repz movsb in Intel x86 ASM. */ -static inline void bytecopy(unsigned char *dest, const 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, const unsigned char *src, int dest_len) { @@ -102,107 +102,76 @@ static int xan_huffman_decode(unsigned char *dest, const unsigned char *src, 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; } +/** + * 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, const 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 (;;) { + while (dest < dest_end) { opcode = *src++; - if ( (opcode & 0x80) == 0 ) { - - offset = *src++; + if (opcode < 0xe0) { + int size2, back; + if ( (opcode & 0x80) == 0 ) { - size = opcode & 3; - if (dest + size > dest_end) - return; - bytecopy(dest, src, size); dest += size; src += size; + size = opcode & 3; - size = ((opcode & 0x1c) >> 2) + 3; - if (dest + size > dest_end) - return; - bytecopy (dest, dest - (((opcode & 0x60) << 3) + offset + 1), size); - dest += size; + back = ((opcode & 0x60) << 3) + *src++ + 1; + size2 = ((opcode & 0x1c) >> 2) + 3; - } else if ( (opcode & 0x40) == 0 ) { + } else if ( (opcode & 0x40) == 0 ) { - byte1 = *src++; - byte2 = *src++; + size = *src >> 6; - 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; + back = (bytestream_get_be16(&src) & 0x3fff) + 1; + size2 = (opcode & 0x3f) + 4; - } else if ( (opcode & 0x20) == 0 ) { - - byte1 = *src++; - byte2 = *src++; - byte3 = *src++; + } else { - size = opcode & 3; - if (dest + size > dest_end) - return; - bytecopy (dest, src, size); dest += size; src += size; + size = opcode & 3; - 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; + 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; - if (dest + size > dest_end) + memcpy(dest, src, size); dest += size; src += size; + if (finish) return; - bytecopy (dest, src, size); dest += size; src += size; } } - - size = opcode & 3; - bytecopy(dest, src, size); dest += size; src += size; } static inline void xan_wc3_output_pixel_run(XanContext *s, @@ -220,13 +189,14 @@ 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; @@ -252,18 +222,21 @@ static inline void xan_wc3_copy_pixel_run(XanContext *s, 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; @@ -368,16 +341,10 @@ static void xan_wc3_decode_frame(XanContext *s) { } } 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); @@ -386,82 +353,206 @@ static void xan_wc3_decode_frame(XanContext *s) { /* 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; } } -static void xan_wc4_decode_frame(XanContext *s) { +#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 *data_size, - const uint8_t *buf, int buf_size) + AVPacket *avpkt) { + const uint8_t *buf = avpkt->data; + int ret, buf_size = avpkt->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; + if (avctx->codec->id == CODEC_ID_XAN_WC3) { + const uint8_t *buf_end = buf + buf_size; + int tag = 0; + while (buf_end - buf > 8 && tag != VGA__TAG) { + unsigned *tmpptr; + uint32_t new_pal; + int size; + int i; + tag = bytestream_get_le32(&buf); + size = bytestream_get_be32(&buf); + size = FFMIN(size, buf_end - buf); + 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(*buf++); + int g = gamma_corr(*buf++); + int b = gamma_corr(*buf++); +#else + int r = gamma_lookup[*buf++]; + int g = gamma_lookup[*buf++]; + int b = gamma_lookup[*buf++]; +#endif + *tmpptr++ = (r << 16) | (g << 8) | b; + } + s->palettes_count++; + break; + case SHOT_TAG: + if (size < 4) + return AVERROR_INVALIDDATA; + new_pal = bytestream_get_le32(&buf); + 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: + buf += size; + break; + } + } + buf_size = buf_end - buf; + } + if ((ret = avctx->get_buffer(avctx, &s->current_frame))) { + av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed\n"); + return ret; } 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; + memcpy(s->current_frame.data[1], s->palettes + s->cur_palette * AVPALETTE_COUNT, AVPALETTE_SIZE); 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); + xan_wc3_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; + /* shuffle frames */ + FFSWAP(AVFrame, s->current_frame, s->last_frame); + /* always report that the buffer was completely consumed */ return buf_size; } -static int xan_decode_end(AVCodecContext *avctx) +static av_cold int xan_decode_end(AVCodecContext *avctx) { XanContext *s = avctx->priv_data; - /* release the last frame */ + /* release the frames */ if (s->last_frame.data[0]) avctx->release_buffer(avctx, &s->last_frame); + 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); + av_freep(&s->palettes); return 0; } -AVCodec xan_wc3_decoder = { +AVCodec ff_xan_wc3_decoder = { "xan_wc3", - CODEC_TYPE_VIDEO, + AVMEDIA_TYPE_VIDEO, CODEC_ID_XAN_WC3, sizeof(XanContext), xan_decode_init, @@ -469,18 +560,6 @@ AVCodec xan_wc3_decoder = { xan_decode_end, xan_decode_frame, CODEC_CAP_DR1, + .long_name = NULL_IF_CONFIG_SMALL("Wing Commander III / Xan"), }; -/* -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, -}; -*/