#include <string.h>
#include "libavutil/random.h"
#include "elbg.h"
#include "avcodec.h"
Go to the source code of this file.
Data Structures | |
| struct | cell_s |
| In the ELBG jargon, a cell is the set of points that are closest to a codebook entry. More... | |
| struct | elbg_data |
| ELBG internal data. More... | |
Defines | |
| #define | DELTA_ERR_MAX 0.1 |
| Precision of the ELBG algorithm (as percentual error). | |
| #define | BIG_PRIME 433494437LL |
Typedefs | |
| typedef struct cell_s | cell |
| In the ELBG jargon, a cell is the set of points that are closest to a codebook entry. | |
Functions | |
| static int | distance_limited (int *a, int *b, int dim, int limit) |
| static void | vect_division (int *res, int *vect, int div, int dim) |
| static int | eval_error_cell (elbg_data *elbg, int *centroid, cell *cells) |
| static int | get_closest_codebook (elbg_data *elbg, int index) |
| static int | get_high_utility_cell (elbg_data *elbg) |
| static int | simple_lbg (int dim, int *centroid[3], int newutility[3], int *points, cell *cells) |
| Implementation of the simple LBG algorithm for just two codebooks. | |
| static void | get_new_centroids (elbg_data *elbg, int huc, int *newcentroid_i, int *newcentroid_p) |
| static void | shift_codebook (elbg_data *elbg, int *indexes, int *newcentroid[3]) |
| Add the points in the low utility cell to its closest cell. | |
| static void | evaluate_utility_inc (elbg_data *elbg) |
| static void | update_utility_and_n_cb (elbg_data *elbg, int idx, int newutility) |
| static void | try_shift_candidate (elbg_data *elbg, int idx[3]) |
| Evaluate if a shift lower the error. | |
| static void | do_shiftings (elbg_data *elbg) |
| Implementation of the ELBG block. | |
| void | ff_init_elbg (int *points, int dim, int numpoints, int *codebook, int numCB, int max_steps, int *closest_cb, AVRandomState *rand_state) |
| Initialize the **codebook vector for the elbg algorithm. | |
| void | ff_do_elbg (int *points, int dim, int numpoints, int *codebook, int numCB, int max_steps, int *closest_cb, AVRandomState *rand_state) |
| Implementation of the Enhanced LBG Algorithm Based on the paper "Neural Networks 14:1219-1237" that can be found in http://citeseer.ist.psu.edu/patan01enhanced.html . | |
Definition in file elbg.c.
| #define BIG_PRIME 433494437LL |
| #define DELTA_ERR_MAX 0.1 |
Precision of the ELBG algorithm (as percentual error).
Definition at line 32 of file elbg.c.
Referenced by ff_do_elbg().
In the ELBG jargon, a cell is the set of points that are closest to a codebook entry.
Not to be confused with a RoQ Video cell.
| static int distance_limited | ( | int * | a, | |
| int * | b, | |||
| int | dim, | |||
| int | limit | |||
| ) | [inline, static] |
Definition at line 58 of file elbg.c.
Referenced by eval_error_cell(), ff_do_elbg(), get_closest_codebook(), shift_codebook(), and simple_lbg().
| static void do_shiftings | ( | elbg_data * | elbg | ) | [static] |
Implementation of the ELBG block.
Definition at line 298 of file elbg.c.
Referenced by ff_do_elbg().
| static void evaluate_utility_inc | ( | elbg_data * | elbg | ) | [static] |
| void ff_do_elbg | ( | int * | points, | |
| int | dim, | |||
| int | numpoints, | |||
| int * | codebook, | |||
| int | numCB, | |||
| int | num_steps, | |||
| int * | closest_cb, | |||
| AVRandomState * | rand_state | |||
| ) |
Implementation of the Enhanced LBG Algorithm Based on the paper "Neural Networks 14:1219-1237" that can be found in http://citeseer.ist.psu.edu/patan01enhanced.html .
| points | Input points. | |
| dim | Dimension of the points. | |
| numpoints | Num of points in **points. | |
| codebook | Pointer to the output codebook. Must be allocated. | |
| numCB | Number of points in the codebook. | |
| num_steps | The maximum number of steps. One step is already a good compromise between time and quality. | |
| closest_cb | Return the closest codebook to each point. Must be allocated. | |
| rand_state | A random number generator state. Should be already initialised by av_random_init. |
Definition at line 346 of file elbg.c.
Referenced by ff_init_elbg(), and generate_codebook().
| void ff_init_elbg | ( | int * | points, | |
| int | dim, | |||
| int | numpoints, | |||
| int * | codebook, | |||
| int | numCB, | |||
| int | num_steps, | |||
| int * | closest_cb, | |||
| AVRandomState * | rand_state | |||
| ) |
Initialize the **codebook vector for the elbg algorithm.
If you have already a codebook and you want to refine it, you shouldn't call this function. If numpoints < 8*numCB this function fills **codebook with random numbers. If not, it calls ff_do_elbg for a (smaller) random sample of the points in **points. Get the same parameters as ff_do_elbg.
Definition at line 319 of file elbg.c.
Referenced by ff_init_elbg(), and generate_codebook().
| static int get_closest_codebook | ( | elbg_data * | elbg, | |
| int | index | |||
| ) | [static] |
| static int get_high_utility_cell | ( | elbg_data * | elbg | ) | [static] |
| static void get_new_centroids | ( | elbg_data * | elbg, | |
| int | huc, | |||
| int * | newcentroid_i, | |||
| int * | newcentroid_p | |||
| ) | [static] |
| static void shift_codebook | ( | elbg_data * | elbg, | |
| int * | indexes, | |||
| int * | newcentroid[3] | |||
| ) | [static] |
Add the points in the low utility cell to its closest cell.
Split the high utility cell, putting the separed points in the (now empty) low utility cell.
| elbg | Internal elbg data | |
| indexes | {luc, huc, cluc} | |
| newcentroid | A vector with the position of the new centroids |
Definition at line 191 of file elbg.c.
Referenced by try_shift_candidate().
| static int simple_lbg | ( | int | dim, | |
| int * | centroid[3], | |||
| int | newutility[3], | |||
| int * | points, | |||
| cell * | cells | |||
| ) | [static] |
Implementation of the simple LBG algorithm for just two codebooks.
Definition at line 120 of file elbg.c.
Referenced by try_shift_candidate().
| static void try_shift_candidate | ( | elbg_data * | elbg, | |
| int | idx[3] | |||
| ) | [static] |
Evaluate if a shift lower the error.
If it does, call shift_codebooks and update elbg->error, elbg->utility and elbg->nearest_cb.
| elbg | Internal elbg data | |
| indexes | {luc (low utility cell, huc (high utility cell), cluc (closest cell to low utility cell)} |
Definition at line 247 of file elbg.c.
Referenced by do_shiftings().
| static void update_utility_and_n_cb | ( | elbg_data * | elbg, | |
| int | idx, | |||
| int | newutility | |||
| ) | [static] |
| static void vect_division | ( | int * | res, | |
| int * | vect, | |||
| int | div, | |||
| int | dim | |||
| ) | [inline, static] |
Definition at line 70 of file elbg.c.
Referenced by ff_do_elbg(), simple_lbg(), and try_shift_candidate().
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