vp3.c

Trolltech公司发布的图形界面操作系统。可在qt-embedded-2.3.10平台上编译为嵌入式图形界面操作系统。

/*
 *
 * Copyright (C) 2003 the ffmpeg project
 *
 * This library 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 of the License, or (at your option) any later version.
 *
 * This library 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 this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * VP3 Video Decoder by Mike Melanson ([e-mail])
 * For more information about the VP3 coding process, visit:
 *   http://www.pcisys.net/~melanson/codecs/
 *
 * Theora decoder by Alex Beregszaszi
 *
 */

/**
 * @file vp3.c
 * On2 VP3 Video Decoder
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "common.h"
#include "avcodec.h"
#include "dsputil.h"
#include "mpegvideo.h"
#include "dsputil.h"

#include "vp3data.h"

#define FRAGMENT_PIXELS 8

/* 
 * Debugging Variables
 * 
 * Define one or more of the following compile-time variables to 1 to obtain
 * elaborate information about certain aspects of the decoding process.
 *
 * KEYFRAMES_ONLY: set this to 1 to only see keyframes (VP3 slideshow mode)
 * DEBUG_VP3: high-level decoding flow
 * DEBUG_INIT: initialization parameters
 * DEBUG_DEQUANTIZERS: display how the dequanization tables are built
 * DEBUG_BLOCK_CODING: unpacking the superblock/macroblock/fragment coding
 * DEBUG_MODES: unpacking the coding modes for individual fragments
 * DEBUG_VECTORS: display the motion vectors
 * DEBUG_TOKEN: display exhaustive information about each DCT token
 * DEBUG_VLC: display the VLCs as they are extracted from the stream
 * DEBUG_DC_PRED: display the process of reversing DC prediction
 * DEBUG_IDCT: show every detail of the IDCT process
 */

#define KEYFRAMES_ONLY 0

#define DEBUG_VP3 0
#define DEBUG_INIT 0
#define DEBUG_DEQUANTIZERS 0
#define DEBUG_BLOCK_CODING 0
#define DEBUG_MODES 0
#define DEBUG_VECTORS 0
#define DEBUG_TOKEN 0
#define DEBUG_VLC 0
#define DEBUG_DC_PRED 0
#define DEBUG_IDCT 0

#if DEBUG_VP3
#define debug_vp3 printf
#else
static inline void debug_vp3(const char *format, ...) { }
#endif

#if DEBUG_INIT
#define debug_init printf
#else
static inline void debug_init(const char *format, ...) { }
#endif

#if DEBUG_DEQUANTIZERS
#define debug_dequantizers printf 
#else
static inline void debug_dequantizers(const char *format, ...) { } 
#endif

#if DEBUG_BLOCK_CODING
#define debug_block_coding printf 
#else
static inline void debug_block_coding(const char *format, ...) { } 
#endif

#if DEBUG_MODES
#define debug_modes printf 
#else
static inline void debug_modes(const char *format, ...) { } 
#endif

#if DEBUG_VECTORS
#define debug_vectors printf 
#else
static inline void debug_vectors(const char *format, ...) { } 
#endif

#if DEBUG_TOKEN 
#define debug_token printf 
#else
static inline void debug_token(const char *format, ...) { } 
#endif

#if DEBUG_VLC
#define debug_vlc printf 
#else
static inline void debug_vlc(const char *format, ...) { } 
#endif

#if DEBUG_DC_PRED
#define debug_dc_pred printf 
#else
static inline void debug_dc_pred(const char *format, ...) { } 
#endif

#if DEBUG_IDCT
#define debug_idct printf 
#else
static inline void debug_idct(const char *format, ...) { } 
#endif

typedef struct Vp3Fragment {
    DCTELEM coeffs[64];
    int coding_method;
    int coeff_count;
    int last_coeff;
    int motion_x;
    int motion_y;
    /* address of first pixel taking into account which plane the fragment
     * lives on as well as the plane stride */
    int first_pixel;
    /* this is the macroblock that the fragment belongs to */
    int macroblock;
} Vp3Fragment;

#define SB_NOT_CODED        0
#define SB_PARTIALLY_CODED  1
#define SB_FULLY_CODED      2

#define MODE_INTER_NO_MV      0
#define MODE_INTRA            1
#define MODE_INTER_PLUS_MV    2
#define MODE_INTER_LAST_MV    3
#define MODE_INTER_PRIOR_LAST 4
#define MODE_USING_GOLDEN     5
#define MODE_GOLDEN_MV        6
#define MODE_INTER_FOURMV     7
#define CODING_MODE_COUNT     8

/* special internal mode */
#define MODE_COPY             8

/* There are 6 preset schemes, plus a free-form scheme */
static int ModeAlphabet[7][CODING_MODE_COUNT] =
{
    /* this is the custom scheme */
    { 0, 0, 0, 0, 0, 0, 0, 0 },

    /* scheme 1: Last motion vector dominates */
    {    MODE_INTER_LAST_MV,    MODE_INTER_PRIOR_LAST,  
         MODE_INTER_PLUS_MV,    MODE_INTER_NO_MV,
         MODE_INTRA,            MODE_USING_GOLDEN,      
         MODE_GOLDEN_MV,        MODE_INTER_FOURMV },

    /* scheme 2 */
    {    MODE_INTER_LAST_MV,    MODE_INTER_PRIOR_LAST,  
         MODE_INTER_NO_MV,      MODE_INTER_PLUS_MV,
         MODE_INTRA,            MODE_USING_GOLDEN,      
         MODE_GOLDEN_MV,        MODE_INTER_FOURMV },

    /* scheme 3 */
    {    MODE_INTER_LAST_MV,    MODE_INTER_PLUS_MV,     
         MODE_INTER_PRIOR_LAST, MODE_INTER_NO_MV,
         MODE_INTRA,            MODE_USING_GOLDEN,      
         MODE_GOLDEN_MV,        MODE_INTER_FOURMV },

    /* scheme 4 */
    {    MODE_INTER_LAST_MV,    MODE_INTER_PLUS_MV,     
         MODE_INTER_NO_MV,      MODE_INTER_PRIOR_LAST,
         MODE_INTRA,            MODE_USING_GOLDEN,      
         MODE_GOLDEN_MV,        MODE_INTER_FOURMV },

    /* scheme 5: No motion vector dominates */
    {    MODE_INTER_NO_MV,      MODE_INTER_LAST_MV,     
         MODE_INTER_PRIOR_LAST, MODE_INTER_PLUS_MV,
         MODE_INTRA,            MODE_USING_GOLDEN,      
         MODE_GOLDEN_MV,        MODE_INTER_FOURMV },

    /* scheme 6 */
    {    MODE_INTER_NO_MV,      MODE_USING_GOLDEN,      
         MODE_INTER_LAST_MV,    MODE_INTER_PRIOR_LAST,
         MODE_INTER_PLUS_MV,    MODE_INTRA,             
         MODE_GOLDEN_MV,        MODE_INTER_FOURMV },

};

#define MIN_DEQUANT_VAL 2

typedef struct Vp3DecodeContext {
    AVCodecContext *avctx;
    int theora, theora_tables;
    int width, height;
    AVFrame golden_frame;
    AVFrame last_frame;
    AVFrame current_frame;
    int keyframe;
    DSPContext dsp;

    int quality_index;
    int last_quality_index;

    int superblock_count;
    int superblock_width;
    int superblock_height;
    int y_superblock_width;
    int y_superblock_height;
    int c_superblock_width;
    int c_superblock_height;
    int u_superblock_start;
    int v_superblock_start;
    unsigned char *superblock_coding;

    int macroblock_count;
    int macroblock_width;
    int macroblock_height;

    int fragment_count;
    int fragment_width;
    int fragment_height;

    Vp3Fragment *all_fragments;
    int u_fragment_start;
    int v_fragment_start;
    
    /* tables */
    uint16_t coded_dc_scale_factor[64];
    uint32_t coded_quality_threshold[64];
    uint16_t coded_intra_y_dequant[64];
    uint16_t coded_intra_c_dequant[64];
    uint16_t coded_inter_dequant[64];

    /* this is a list of indices into the all_fragments array indicating
     * which of the fragments are coded */
    int *coded_fragment_list;
    int coded_fragment_list_index;
    int pixel_addresses_inited;

    VLC dc_vlc[16];
    VLC ac_vlc_1[16];
    VLC ac_vlc_2[16];
    VLC ac_vlc_3[16];
    VLC ac_vlc_4[16];

    int16_t intra_y_dequant[64];
    int16_t intra_c_dequant[64];
    int16_t inter_dequant[64];

    /* This table contains superblock_count * 16 entries. Each set of 16
     * numbers corresponds to the fragment indices 0..15 of the superblock.
     * An entry will be -1 to indicate that no entry corresponds to that
     * index. */
    int *superblock_fragments;

    /* This table contains superblock_count * 4 entries. Each set of 4
     * numbers corresponds to the macroblock indices 0..3 of the superblock.
     * An entry will be -1 to indicate that no entry corresponds to that
     * index. */
    int *superblock_macroblocks;

    /* This table contains macroblock_count * 6 entries. Each set of 6
     * numbers corresponds to the fragment indices 0..5 which comprise
     * the macroblock (4 Y fragments and 2 C fragments). */
    int *macroblock_fragments;
    /* This is an array that indicates how a particular macroblock 
     * is coded. */
    unsigned char *macroblock_coding;

    int first_coded_y_fragment;
    int first_coded_c_fragment;
    int last_coded_y_fragment;
    int last_coded_c_fragment;

    uint8_t edge_emu_buffer[9*2048]; //FIXME dynamic alloc
    uint8_t qscale_table[2048]; //FIXME dynamic alloc (width+15)/16
} Vp3DecodeContext;

/************************************************************************
 * VP3 I/DCT
 ************************************************************************/

#define IdctAdjustBeforeShift 8
#define xC1S7 64277
#define xC2S6 60547
#define xC3S5 54491
#define xC4S4 46341
#define xC5S3 36410
#define xC6S2 25080
#define xC7S1 12785

void vp3_idct_c(int16_t *input_data, int16_t *dequant_matrix, 
    int16_t *output_data)
{
    int32_t intermediate_data[64];
    int32_t *ip = intermediate_data;
    int16_t *op = output_data;

    int32_t A_, B_, C_, D_, _Ad, _Bd, _Cd, _Dd, E_, F_, G_, H_;
    int32_t _Ed, _Gd, _Add, _Bdd, _Fd, _Hd;
    int32_t t1, t2;

    int i, j;

    debug_idct("raw coefficient block:\n");
    for (i = 0; i < 8; i++) {
        for (j = 0; j < 8; j++) {
            debug_idct(" %5d", input_data[i * 8 + j]);
        }
        debug_idct("\n");
    }
    debug_idct("\n");

    for (i = 0; i < 64; i++) {
        j = dezigzag_index[i];
        intermediate_data[j] = dequant_matrix[i] * input_data[i];
    }

    debug_idct("dequantized block:\n");
    for (i = 0; i < 8; i++) {
        for (j = 0; j < 8; j++) {
            debug_idct(" %5d", intermediate_data[i * 8 + j]);
        }
        debug_idct("\n");
    }
    debug_idct("\n");

    /* Inverse DCT on the rows now */
    for (i = 0; i < 8; i++) {
        /* Check for non-zero values */
        if ( ip[0] | ip[1] | ip[2] | ip[3] | ip[4] | ip[5] | ip[6] | ip[7] ) {
            t1 = (int32_t)(xC1S7 * ip[1]);
            t2 = (int32_t)(xC7S1 * ip[7]);
            t1 >>= 16;
            t2 >>= 16;
            A_ = t1 + t2;

            t1 = (int32_t)(xC7S1 * ip[1]);
            t2 = (int32_t)(xC1S7 * ip[7]);
            t1 >>= 16;
            t2 >>= 16;
            B_ = t1 - t2;

            t1 = (int32_t)(xC3S5 * ip[3]);
            t2 = (int32_t)(xC5S3 * ip[5]);
            t1 >>= 16;
            t2 >>= 16;
            C_ = t1 + t2;

            t1 = (int32_t)(xC3S5 * ip[5]);
            t2 = (int32_t)(xC5S3 * ip[3]);
            t1 >>= 16;
            t2 >>= 16;
            D_ = t1 - t2;


            t1 = (int32_t)(xC4S4 * (A_ - C_));
            t1 >>= 16;
            _Ad = t1;

            t1 = (int32_t)(xC4S4 * (B_ - D_));
            t1 >>= 16;
            _Bd = t1;


            _Cd = A_ + C_;
            _Dd = B_ + D_;

            t1 = (int32_t)(xC4S4 * (ip[0] + ip[4]));
            t1 >>= 16;
            E_ = t1;

            t1 = (int32_t)(xC4S4 * (ip[0] - ip[4]));
            t1 >>= 16;
            F_ = t1;

            t1 = (int32_t)(xC2S6 * ip[2]);
            t2 = (int32_t)(xC6S2 * ip[6]);
            t1 >>= 16;
            t2 >>= 16;
            G_ = t1 + t2;

            t1 = (int32_t)(xC6S2 * ip[2]);