libdirac_encoder/rate_control.h

   1 /* ***** BEGIN LICENSE BLOCK *****
   2 *
   3 * $Id$ $Name$
   4 *
   5 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   6 *
   7 * The contents of this file are subject to the Mozilla Public License
   8 * Version 1.1 (the "License"); you may not use this file except in compliance
   9 * with the License. You may obtain a copy of the License at
  10 * http://www.mozilla.org/MPL/
  11 *
  12 * Software distributed under the License is distributed on an "AS IS" basis,
  13 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
  14 * the specific language governing rights and limitations under the License.
  15 *
  16 * The Original Code is BBC Research and Development code.
  17 *
  18 * The Initial Developer of the Original Code is the British Broadcasting
  19 * Corporation.
  20 * Portions created by the Initial Developer are Copyright (C) 2004.
  21 * All Rights Reserved.
  22 *
  23 * Contributor(s): Myo Tun (Original Author, myo.tun@brunel.ac.uk)
  24 *                 Jonathan Loo (Jonathan.Loo@brunel.ac.uk)
  25 *          School of Engineering and Design, Brunel University, UK
  26 *
  27 * Alternatively, the contents of this file may be used under the terms of
  28 * the GNU General Public License Version 2 (the "GPL"), or the GNU Lesser
  29 * Public License Version 2.1 (the "LGPL"), in which case the provisions of
  30 * the GPL or the LGPL are applicable instead of those above. If you wish to
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  35 * or LGPL. If you do not delete the provisions above, a recipient may use
  36 * your version of this file under the terms of any one of the MPL, the GPL
  37 * or the LGPL.
  38 * ***** END LICENSE BLOCK ***** */
  39
  40
  41 //Compression of an individual component,
  42 //after motion compensation if appropriate
  43 //////////////////////////////////////////
  44
  45 #ifndef _RATE_CONTROL_H_
  46 #define _RATE_CONTROL_H_
  47
  48 #include <libdirac_common/common.h>
  49
  50 namespace dirac
  51 {
  52     class FrameComplexity
  53     {
  54     public:
  55         //! Default constructor
  56         FrameComplexity();
  57
  58         //! Return the complexity of I frame
  59         int IComplexity() {return m_XI;}
  60
  61         //! Return the complexity of L1 frame
  62         int L1Complexity() {return m_XL1;}
  63
  64         //! Return the complexity of L2 frame
  65         int L2Complexity() {return m_XL2;}
  66
  67         //! Set the complexity of I frame
  68         void SetIComplexity(int cpx) {m_XI = cpx;}
  69
  70         //! Set the complexity of L1 frame
  71         void SetL1Complexity(int cpx) {m_XL1 = cpx;}
  72
  73         //! Set the complexity of L2 frame
  74         void SetL2Complexity(int cpx) {m_XL2 = cpx;}
  75
  76
  77     private:
  78
  79         //! Complexity of I frame
  80         int m_XI;
  81
  82         //! Complexity of L1 frame
  83         int m_XL1;
  84
  85         //! Complexity of L2 frame
  86         int m_XL2;
  87     };
  88
  89
  90     //! A clas for allocation the bits to each and every types of frames in a GOP
  91     class RateController
  92     {
  93     public:
  94
  95         //! Default constructor
  96         RateController(int trate, SourceParams& srcp, EncoderParams& encp);
  97
  98
  99         //! Calculate the Quality factor of the next frame to encode
 100         void CalcNextQualFactor(const PictureParams& fparams, int num_bits);
 101
 102         //! Calculate the Quality factor of the next I frame to encode
 103         void CalcNextIntraQualFactor();
 104
 105         //! Use the long-term average intra quality factor
 106         void SetCutPictureQualFactor();
 107
 108         //! Return I frame qf
 109         double IntraQualFactor() {return m_I_qf;}
 110
 111         //! Return qf
 112         double QualFactor() {return m_qf;}
 113
 114         //! Report the allocation to picture types
 115         void Report();
 116
 117
 118     private:
 119
 120         double TargetSubgroupRate();
 121
 122         double ProjectedSubgroupRate();
 123
 124         //! Allocate the bits to each type of frame in a GOP
 125         void Allocate(const int fnum);
 126
 127         //! Calculate the total number of bits in a GOP
 128         void CalcTotalBits(const SourceParams& sourceparams);
 129
 130         //! Set the value of Current IQF
 131         void SetIntraQualFactor(double value){m_I_qf = value;}
 132
 133         //! Set the number of I, L1 and L2 frames in the GOP
 134         void SetFrameDistribution();
 135
 136         //! Review the quality factor to make sure it's being set sensibly
 137         float ReviewQualityFactor( const float qfac, const long int num_bits );
 138
 139         //! Clip the quality factor to something sensible
 140         float ClipQualityFactor( const float qfac );
 141
 142         //! Update the internal decoder buffer model
 143         void UpdateBuffer( const long int num_bits );
 144
 145
 146     private:
 147
 148         //! Current Quality Factor
 149         double m_qf;
 150
 151         //! I frame Quality Factor
 152         double m_I_qf;
 153
 154         //! Long-term average of I frame Quality Factor
 155         double m_I_qf_long_term;
 156
 157         //! Target bit rate in kbps
 158         const int m_target_rate;
 159
 160         //! Number of bits for I frame
 161         long int m_Iframe_bits;
 162
 163         //! Number of bits for L1 frame
 164         long int m_L1frame_bits;
 165
 166         //! Number of bits for L2 frame
 167         long int m_L2frame_bits;
 168
 169         //! Number of I frames
 170         int m_num_Iframe;
 171
 172         //! Number of L1 frames
 173         int m_num_L1frame;
 174
 175         //! Number of L2 frames
 176         int m_num_L2frame;
 177
 178         //! Total Number of bits in a GOP
 179         long int m_total_GOP_bits;
 180
 181         //! Mean number of bits in a picture
 182         long int m_picture_bits;
 183
 184         //! Size of the decoded bit buffer
 185         const long int m_buffer_size;
 186
 187         //! Number of bits in the buffer
 188         long int m_buffer_bits;
 189
 190         //! The old buffer occupancy
 191         long int m_old_buffer_bits;
 192
 193         //! The rate of change of buffer occupancy
 194         double m_buffer_rate_of_change;
 195
 196         //! The target number of bits for the current GOP
 197         long int m_GOP_target;
 198
 199         //! The duration of a GOP
 200         double m_GOP_duration;
 201
 202         //! A reference to the encoder parameters
 203         EncoderParams& m_encparams;
 204
 205         //! A class to hold the frame complexity object
 206         FrameComplexity m_frame_complexity;
 207
 208         //! A frame counter, giving the position within a subgroup
 209         int m_fcount;
 210
 211         // Indicated whether a sequence is being coded intra only or not
 212         bool m_intra_only;
 213
 214         // Sum of complexity of L2 frames
 215         int m_L2_complexity_sum;
 216
 217     };
 218
 219
 220 }// namespace dirac
 221 #endif