Commit ddcf4b5d authored by Vitor Sessak's avatar Vitor Sessak Committed by Benoit Fouet

Codebook generator using the ELBG algorithm

patch by Vitor: printf(vitor%d gmail com, 1001)
original thread: Re: [FFmpeg-devel] [PATCH] Add a codebook generator
                 (was: [PATCH] RoQ video encoder, take 2)
date: 05/28/2007 01:21 PM

Originally committed as revision 9196 to svn://
parent 1963f5e3
......@@ -86,6 +86,7 @@ version <next>
- Renderware TXD demuxer and decoder
- extern C declarations for C++ removed from headers
- sws_flags command line option
- codebook generator
version 0.4.9-pre1:
This diff is collapsed.
* Copyright (C) 2007 Vitor <>
* 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
* 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
#include "random.h"
* Implementation of the Enhanced LBG Algorithm
* Based on the paper "Neural Networks 14:1219-1237" that can be found in
* .
* @param points Input points.
* @param dim Dimension of the points.
* @param numpoints Num of points in **points.
* @param codebook Pointer to the output codebook. Must be allocated.
* @param numCB Number of points in the codebook.
* @param num_steps The maximum number of steps. One step is already a good compromise between time and quality.
* @param closest_cb Return the closest codebook to each point. Must be allocated.
* @param rand_state A random number generator state. Should be already initialised by av_init_random.
void ff_do_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.
void ff_init_elbg(int *points, int dim, int numpoints, int *codebook,
int numCB, int num_steps, int *closest_cb,
AVRandomState *rand_state);
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