libavcodec/vp56.h - vendor/opensource/ffmpeg - Git at Google

 /**
  * @file libavcodec/vp56.h
  * VP5 and VP6 compatible video decoder (common features)
  *
  * Copyright (C) 2006  Aurelien Jacobs <aurel@gnuage.org>
  *
  * 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
  */

 #ifndef AVCODEC_VP56_H
 #define AVCODEC_VP56_H

 #include "vp56data.h"
 #include "dsputil.h"
 #include "bitstream.h"
 #include "bytestream.h"


 typedef struct vp56_context VP56Context;
 typedef struct vp56_mv VP56mv;

 typedef void (*VP56ParseVectorAdjustment)(VP56Context *s,
                                           VP56mv *vect);
 typedef int  (*VP56Adjust)(int v, int t);
 typedef void (*VP56Filter)(VP56Context *s, uint8_t *dst, uint8_t *src,
                            int offset1, int offset2, int stride,
                            VP56mv mv, int mask, int select, int luma);
 typedef void (*VP56ParseCoeff)(VP56Context *s);
 typedef void (*VP56DefaultModelsInit)(VP56Context *s);
 typedef void (*VP56ParseVectorModels)(VP56Context *s);
 typedef void (*VP56ParseCoeffModels)(VP56Context *s);
 typedef int  (*VP56ParseHeader)(VP56Context *s, const uint8_t *buf,
                                 int buf_size, int *golden_frame);

 typedef struct {
     int high;
     int bits;
     const uint8_t *buffer;
     unsigned long code_word;
 } VP56RangeCoder;

 typedef struct {
     uint8_t not_null_dc;
     VP56Frame ref_frame;
     DCTELEM dc_coeff;
 } VP56RefDc;

 struct vp56_mv {
     int x;
     int y;
 };

 typedef struct {
     uint8_t type;
     VP56mv mv;
 } VP56Macroblock;

 typedef struct {
     uint8_t coeff_reorder[64];       /* used in vp6 only */
     uint8_t coeff_index_to_pos[64];  /* used in vp6 only */
     uint8_t vector_sig[2];           /* delta sign */
     uint8_t vector_dct[2];           /* delta coding types */
     uint8_t vector_pdi[2][2];        /* predefined delta init */
     uint8_t vector_pdv[2][7];        /* predefined delta values */
     uint8_t vector_fdv[2][8];        /* 8 bit delta value definition */
     uint8_t coeff_dccv[2][11];       /* DC coeff value */
     uint8_t coeff_ract[2][3][6][11]; /* Run/AC coding type and AC coeff value */
     uint8_t coeff_acct[2][3][3][6][5];/* vp5 only AC coding type for coding group < 3 */
     uint8_t coeff_dcct[2][36][5];    /* DC coeff coding type */
     uint8_t coeff_runv[2][14];       /* run value (vp6 only) */
     uint8_t mb_type[3][10][10];      /* model for decoding MB type */
     uint8_t mb_types_stats[3][10][2];/* contextual, next MB type stats */
 } VP56Model;

 struct vp56_context {
     AVCodecContext *avctx;
     DSPContext dsp;
     ScanTable scantable;
     AVFrame frames[4];
     AVFrame *framep[6];
     uint8_t *edge_emu_buffer_alloc;
     uint8_t *edge_emu_buffer;
     VP56RangeCoder c;
     VP56RangeCoder cc;
     VP56RangeCoder *ccp;
     int sub_version;

     /* frame info */
     int plane_width[4];
     int plane_height[4];
     int mb_width;   /* number of horizontal MB */
     int mb_height;  /* number of vertical MB */
     int block_offset[6];

     int quantizer;
     uint16_t dequant_dc;
     uint16_t dequant_ac;

     /* DC predictors management */
     VP56RefDc *above_blocks;
     VP56RefDc left_block[4];
     int above_block_idx[6];
     DCTELEM prev_dc[3][3];    /* [plan][ref_frame] */

     /* blocks / macroblock */
     VP56mb mb_type;
     VP56Macroblock *macroblocks;
     DECLARE_ALIGNED_16(DCTELEM, block_coeff[6][64]);

     /* motion vectors */
     VP56mv mv[6];  /* vectors for each block in MB */
     VP56mv vector_candidate[2];
     int vector_candidate_pos;

     /* filtering hints */
     int filter_header;               /* used in vp6 only */
     int deblock_filtering;
     int filter_selection;
     int filter_mode;
     int max_vector_length;
     int sample_variance_threshold;

     uint8_t coeff_ctx[4][64];              /* used in vp5 only */
     uint8_t coeff_ctx_last[4];             /* used in vp5 only */

     int has_alpha;

     /* upside-down flipping hints */
     int flip;  /* are we flipping ? */
     int frbi;  /* first row block index in MB */
     int srbi;  /* second row block index in MB */
     int stride[4];  /* stride for each plan */

     const uint8_t *vp56_coord_div;
     VP56ParseVectorAdjustment parse_vector_adjustment;
     VP56Adjust adjust;
     VP56Filter filter;
     VP56ParseCoeff parse_coeff;
     VP56DefaultModelsInit default_models_init;
     VP56ParseVectorModels parse_vector_models;
     VP56ParseCoeffModels parse_coeff_models;
     VP56ParseHeader parse_header;

     VP56Model *modelp;
     VP56Model models[2];

     /* huffman decoding */
     int use_huffman;
     GetBitContext gb;
     VLC dccv_vlc[2];
     VLC runv_vlc[2];
     VLC ract_vlc[2][3][6];
     unsigned int nb_null[2][2];       /* number of consecutive NULL DC/AC */
 };


 void vp56_init(AVCodecContext *avctx, int flip, int has_alpha);
 int vp56_free(AVCodecContext *avctx);
 void vp56_init_dequant(VP56Context *s, int quantizer);
 int vp56_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
                       const uint8_t *buf, int buf_size);


 /**
  * vp56 specific range coder implementation
  */

 static inline void vp56_init_range_decoder(VP56RangeCoder *c,
                                            const uint8_t *buf, int buf_size)
 {
     c->high = 255;
     c->bits = 8;
     c->buffer = buf;
     c->code_word = bytestream_get_be16(&c->buffer);
 }

 static inline int vp56_rac_get_prob(VP56RangeCoder *c, uint8_t prob)
 {
     unsigned int low = 1 + (((c->high - 1) * prob) / 256);
     unsigned int low_shift = low << 8;
     int bit = c->code_word >= low_shift;

     if (bit) {
         c->high -= low;
         c->code_word -= low_shift;
     } else {
         c->high = low;
     }

     /* normalize */
     while (c->high < 128) {
         c->high <<= 1;
         c->code_word <<= 1;
         if (--c->bits == 0) {
             c->bits = 8;
             c->code_word |= *c->buffer++;
         }
     }
     return bit;
 }

 static inline int vp56_rac_get(VP56RangeCoder *c)
 {
     /* equiprobable */
     int low = (c->high + 1) >> 1;
     unsigned int low_shift = low << 8;
     int bit = c->code_word >= low_shift;
     if (bit) {
         c->high = (c->high - low) << 1;
         c->code_word -= low_shift;
     } else {
         c->high = low << 1;
     }

     /* normalize */
     c->code_word <<= 1;
     if (--c->bits == 0) {
         c->bits = 8;
         c->code_word |= *c->buffer++;
     }
     return bit;
 }

 static inline int vp56_rac_gets(VP56RangeCoder *c, int bits)
 {
     int value = 0;

     while (bits--) {
         value = (value << 1) | vp56_rac_get(c);
     }

     return value;
 }

 static inline int vp56_rac_gets_nn(VP56RangeCoder *c, int bits)
 {
     int v = vp56_rac_gets(c, 7) << 1;
     return v + !v;
 }

 static inline int vp56_rac_get_tree(VP56RangeCoder *c,
                                     const VP56Tree *tree,
                                     const uint8_t *probs)
 {
     while (tree->val > 0) {
         if (vp56_rac_get_prob(c, probs[tree->prob_idx]))
             tree += tree->val;
         else
             tree++;
     }
     return -tree->val;
 }

 #endif /* AVCODEC_VP56_H */
	/**
	* @file libavcodec/vp56.h
	* VP5 and VP6 compatible video decoder (common features)
	*
	* Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org>
	*
	* 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
	*/

	#ifndef AVCODEC_VP56_H
	#define AVCODEC_VP56_H

	#include "vp56data.h"
	#include "dsputil.h"
	#include "bitstream.h"
	#include "bytestream.h"


	typedef struct vp56_context VP56Context;
	typedef struct vp56_mv VP56mv;

	typedef void (VP56ParseVectorAdjustment)(VP56Context s,
	VP56mv *vect);
	typedef int (*VP56Adjust)(int v, int t);
	typedef void (VP56Filter)(VP56Context s, uint8_t dst, uint8_t src,
	int offset1, int offset2, int stride,
	VP56mv mv, int mask, int select, int luma);
	typedef void (VP56ParseCoeff)(VP56Context s);
	typedef void (VP56DefaultModelsInit)(VP56Context s);
	typedef void (VP56ParseVectorModels)(VP56Context s);
	typedef void (VP56ParseCoeffModels)(VP56Context s);
	typedef int (VP56ParseHeader)(VP56Context s, const uint8_t *buf,
	int buf_size, int *golden_frame);

	typedef struct {
	int high;
	int bits;
	const uint8_t *buffer;
	unsigned long code_word;
	} VP56RangeCoder;

	typedef struct {
	uint8_t not_null_dc;
	VP56Frame ref_frame;
	DCTELEM dc_coeff;
	} VP56RefDc;

	struct vp56_mv {
	int x;
	int y;
	};

	typedef struct {
	uint8_t type;
	VP56mv mv;
	} VP56Macroblock;

	typedef struct {
	uint8_t coeff_reorder[64]; /* used in vp6 only */
	uint8_t coeff_index_to_pos[64]; /* used in vp6 only */
	uint8_t vector_sig[2]; /* delta sign */
	uint8_t vector_dct[2]; /* delta coding types */
	uint8_t vector_pdi[2][2]; /* predefined delta init */
	uint8_t vector_pdv[2][7]; /* predefined delta values */
	uint8_t vector_fdv[2][8]; /* 8 bit delta value definition */
	uint8_t coeff_dccv[2][11]; /* DC coeff value */
	uint8_t coeff_ract[2][3][6][11]; /* Run/AC coding type and AC coeff value */
	uint8_t coeff_acct[2][3][3][6][5];/* vp5 only AC coding type for coding group < 3 */
	uint8_t coeff_dcct[2][36][5]; /* DC coeff coding type */
	uint8_t coeff_runv[2][14]; /* run value (vp6 only) */
	uint8_t mb_type[3][10][10]; /* model for decoding MB type */
	uint8_t mb_types_stats[3][10][2];/* contextual, next MB type stats */
	} VP56Model;

	struct vp56_context {
	AVCodecContext *avctx;
	DSPContext dsp;
	ScanTable scantable;
	AVFrame frames[4];
	AVFrame *framep[6];
	uint8_t *edge_emu_buffer_alloc;
	uint8_t *edge_emu_buffer;
	VP56RangeCoder c;
	VP56RangeCoder cc;
	VP56RangeCoder *ccp;
	int sub_version;

	/* frame info */
	int plane_width[4];
	int plane_height[4];
	int mb_width; /* number of horizontal MB */
	int mb_height; /* number of vertical MB */
	int block_offset[6];

	int quantizer;
	uint16_t dequant_dc;
	uint16_t dequant_ac;

	/* DC predictors management */
	VP56RefDc *above_blocks;
	VP56RefDc left_block[4];
	int above_block_idx[6];
	DCTELEM prev_dc[3][3]; /* [plan][ref_frame] */

	/* blocks / macroblock */
	VP56mb mb_type;
	VP56Macroblock *macroblocks;
	DECLARE_ALIGNED_16(DCTELEM, block_coeff[6][64]);

	/* motion vectors */
	VP56mv mv[6]; /* vectors for each block in MB */
	VP56mv vector_candidate[2];
	int vector_candidate_pos;

	/* filtering hints */
	int filter_header; /* used in vp6 only */
	int deblock_filtering;
	int filter_selection;
	int filter_mode;
	int max_vector_length;
	int sample_variance_threshold;

	uint8_t coeff_ctx[4][64]; /* used in vp5 only */
	uint8_t coeff_ctx_last[4]; /* used in vp5 only */

	int has_alpha;

	/* upside-down flipping hints */
	int flip; /* are we flipping ? */
	int frbi; /* first row block index in MB */
	int srbi; /* second row block index in MB */
	int stride[4]; /* stride for each plan */

	const uint8_t *vp56_coord_div;
	VP56ParseVectorAdjustment parse_vector_adjustment;
	VP56Adjust adjust;
	VP56Filter filter;
	VP56ParseCoeff parse_coeff;
	VP56DefaultModelsInit default_models_init;
	VP56ParseVectorModels parse_vector_models;
	VP56ParseCoeffModels parse_coeff_models;
	VP56ParseHeader parse_header;

	VP56Model *modelp;
	VP56Model models[2];

	/* huffman decoding */
	int use_huffman;
	GetBitContext gb;
	VLC dccv_vlc[2];
	VLC runv_vlc[2];
	VLC ract_vlc[2][3][6];
	unsigned int nb_null[2][2]; /* number of consecutive NULL DC/AC */
	};


	void vp56_init(AVCodecContext *avctx, int flip, int has_alpha);
	int vp56_free(AVCodecContext *avctx);
	void vp56_init_dequant(VP56Context *s, int quantizer);
	int vp56_decode_frame(AVCodecContext avctx, void data, int *data_size,
	const uint8_t *buf, int buf_size);


	/**
	* vp56 specific range coder implementation
	*/

	static inline void vp56_init_range_decoder(VP56RangeCoder *c,
	const uint8_t *buf, int buf_size)
	{
	c->high = 255;
	c->bits = 8;
	c->buffer = buf;
	c->code_word = bytestream_get_be16(&c->buffer);
	}

	static inline int vp56_rac_get_prob(VP56RangeCoder *c, uint8_t prob)
	{
	unsigned int low = 1 + (((c->high - 1) * prob) / 256);
	unsigned int low_shift = low << 8;
	int bit = c->code_word >= low_shift;

	if (bit) {
	c->high -= low;
	c->code_word -= low_shift;
	} else {
	c->high = low;
	}

	/* normalize */
	while (c->high < 128) {
	c->high <<= 1;
	c->code_word <<= 1;
	if (--c->bits == 0) {
	c->bits = 8;
	c->code_word \|= *c->buffer++;
	}
	}
	return bit;
	}

	static inline int vp56_rac_get(VP56RangeCoder *c)
	{
	/* equiprobable */
	int low = (c->high + 1) >> 1;
	unsigned int low_shift = low << 8;
	int bit = c->code_word >= low_shift;
	if (bit) {
	c->high = (c->high - low) << 1;
	c->code_word -= low_shift;
	} else {
	c->high = low << 1;
	}

	/* normalize */
	c->code_word <<= 1;
	if (--c->bits == 0) {
	c->bits = 8;
	c->code_word \|= *c->buffer++;
	}
	return bit;
	}

	static inline int vp56_rac_gets(VP56RangeCoder *c, int bits)
	{
	int value = 0;

	while (bits--) {
	value = (value << 1) \| vp56_rac_get(c);
	}

	return value;
	}

	static inline int vp56_rac_gets_nn(VP56RangeCoder *c, int bits)
	{
	int v = vp56_rac_gets(c, 7) << 1;
	return v + !v;
	}

	static inline int vp56_rac_get_tree(VP56RangeCoder *c,
	const VP56Tree *tree,
	const uint8_t *probs)
	{
	while (tree->val > 0) {
	if (vp56_rac_get_prob(c, probs[tree->prob_idx]))
	tree += tree->val;
	else
	tree++;
	}
	return -tree->val;
	}

	#endif /* AVCODEC_VP56_H */