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mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-23 12:43:46 +02:00

fixed some return values and deprecated CODEC_TYPE_VIDEO.

dithering (faster) along a linear gradient now.

Originally committed as revision 24898 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Tobias Bindhammer 2010-08-24 14:02:31 +00:00
parent ac9c19da66
commit bb07ab7cf2
5 changed files with 119 additions and 43 deletions

50
libavcodec/a64colors.h Normal file
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@ -0,0 +1,50 @@
/*
* a64 video encoder - tables used by 64enc
* Copyright (c) 2009 Tobias Bindhammer
*
* 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
*/
/**
* @file
* a64 video encoder - c64 colors in rgb
*/
#ifndef AVCODEC_A64COLORS_H
#define AVCODEC_A64COLORS_H
/* c64 palette in RGB */
static const uint8_t a64_palette[16][3] = {
{0x00, 0x00, 0x00},
{0xff, 0xff, 0xff},
{0x68, 0x37, 0x2b},
{0x70, 0xa4, 0xb2},
{0x6f, 0x3d, 0x86},
{0x58, 0x8d, 0x43},
{0x35, 0x28, 0x79},
{0xb8, 0xc7, 0x6f},
{0x6f, 0x4f, 0x25},
{0x43, 0x39, 0x00},
{0x9a, 0x67, 0x59},
{0x44, 0x44, 0x44},
{0x6c, 0x6c, 0x6c},
{0x9a, 0xd2, 0x84},
{0x6c, 0x5e, 0xb5},
{0x95, 0x95, 0x95},
};
#endif /* AVCODEC_A64COLORS_H */

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@ -45,6 +45,8 @@ typedef struct A64Context {
int *mc_meta_charset;
int *mc_charmap;
int *mc_best_cb;
int *mc_charset;
int mc_luma_vals[5];
} A64Context;
#endif /* AVCODEC_A64ENC_H */

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@ -25,11 +25,16 @@
*/
#include "a64enc.h"
#include "a64colors.h"
#include "a64tables.h"
#include "elbg.h"
#include "libavutil/intreadwrite.h"
#define DITHERSTEPS 8
#define CHARSET_CHARS 256
/* gray gradient */
static const int mc_colors[5]={0x0,0xb,0xc,0xf,0x1};
static void to_meta_with_crop(AVCodecContext *avctx, AVFrame *p, int *dest)
{
@ -63,64 +68,72 @@ static void render_charset(AVCodecContext *avctx, uint8_t *charset,
A64Context *c = avctx->priv_data;
uint8_t row1;
int charpos, x, y;
int pix;
int dither;
int index1, index2;
int a, b;
uint8_t pix;
int lowdiff, highdiff;
int maxindex = c->mc_use_5col + 3;
int maxsteps = DITHERSTEPS * maxindex + 1;
int *best_cb = c->mc_best_cb;
static uint8_t index1[256];
static uint8_t index2[256];
static uint8_t dither[256];
int i;
int distance;
/* now reduce colors first */
for (x = 0; x < 256 * 32; x++) best_cb[x] = best_cb[x] * maxsteps / 255;
/* generate lookup-tables for dither and index before looping */
i = 0;
for (a=0; a < 256; a++) {
if(i < 4 && a == c->mc_luma_vals[i+1]) {
distance = c->mc_luma_vals[i+1] - c->mc_luma_vals[i];
for(b = 0; b <= distance; b++) {
dither[c->mc_luma_vals[i]+b] = b * (DITHERSTEPS - 1) / distance;
}
i++;
}
if(i >=4 ) dither[a] = 0;
index1[a] = i;
index2[a] = FFMIN(i+1, 4);
}
/* and render charset */
for (charpos = 0; charpos < 256; charpos++) {
for (charpos = 0; charpos < CHARSET_CHARS; charpos++) {
lowdiff = 0;
highdiff = 0;
for (y = 0; y < 8; y++) {
row1 = 0;
for (x = 0; x < 4; x++) {
pix = best_cb[y * 4 + x];
dither = pix % DITHERSTEPS;
index1 = pix / DITHERSTEPS;
index2 = FFMIN(index1 + 1, maxindex);
if (pix > 3 * DITHERSTEPS)
highdiff += pix - 3 * DITHERSTEPS;
if (pix < DITHERSTEPS)
lowdiff += DITHERSTEPS - pix;
/* accumulate error for brightest/darkest color */
if (index1[pix] >= 3)
highdiff += pix - c->mc_luma_vals[3];
if (index1[pix] < 1)
lowdiff += c->mc_luma_vals[1] - pix;
row1 <<= 2;
if (prep_dither_patterns[dither][y & 3][x & 3]) {
row1 |= 3-(index2 & 3);
} else {
row1 |= 3-(index1 & 3);
}
}
charset[y] = row1;
}
/* are we in 5col mode and need to adjust pixels? */
if (c->mc_use_5col && highdiff > 0 && lowdiff > 0) {
if (multi_dither_patterns[dither[pix]][(y & 3)][x & 3])
row1 |= 3-(index2[pix] & 3);
else
row1 |= 3-(index1[pix] & 3);
}
charset[y+0x000] = row1;
}
/* do we need to adjust pixels? */
if (highdiff > 0 && lowdiff > 0) {
if (lowdiff > highdiff) {
for (x = 0; x < 32; x++)
best_cb[x] = FFMIN(3 * DITHERSTEPS, best_cb[x]);
best_cb[x] = FFMIN(c->mc_luma_vals[3], best_cb[x]);
} else {
for (x = 0; x < 32; x++)
best_cb[x] = FFMAX(DITHERSTEPS, best_cb[x]);
best_cb[x] = FFMAX(c->mc_luma_vals[1], best_cb[x]);
}
charpos--; /* redo char */
charpos--; /* redo now adjusted char */
/* no adjustment needed, all fine */
} else {
/* advance pointers */
best_cb += 32;
charset += 8;
if (highdiff > 0) {
colrammap[charpos] = 0x9;
} else {
colrammap[charpos] = 0x8;
}
/* remember colorram value */
colrammap[charpos] = (highdiff > 0) + 8;
}
}
}
@ -131,12 +144,14 @@ static av_cold int a64multi_close_encoder(AVCodecContext *avctx)
av_free(c->mc_meta_charset);
av_free(c->mc_best_cb);
av_free(c->mc_charmap);
av_free(c->mc_charset);
return 0;
}
static av_cold int a64multi_init_encoder(AVCodecContext *avctx)
{
A64Context *c = avctx->priv_data;
int a;
av_lfg_init(&c->randctx, 1);
if (avctx->global_quality < 1) {
@ -147,11 +162,19 @@ static av_cold int a64multi_init_encoder(AVCodecContext *avctx)
av_log(avctx, AV_LOG_INFO, "charset lifetime set to %d frame(s)\n", c->mc_lifetime);
/* precalc luma values for later use */
for (a = 0; a < 5; a++) {
c->mc_luma_vals[a]=a64_palette[mc_colors[a]][0] * 0.30 +
a64_palette[mc_colors[a]][1] * 0.59 +
a64_palette[mc_colors[a]][2] * 0.11;
}
c->mc_frame_counter = 0;
c->mc_use_5col = avctx->codec->id == CODEC_ID_A64_MULTI5;
c->mc_meta_charset = av_malloc(32000 * c->mc_lifetime * sizeof(int));
c->mc_best_cb = av_malloc(256 * 32 * sizeof(int));
c->mc_best_cb = av_malloc(CHARSET_CHARS * 32 * sizeof(int));
c->mc_charmap = av_malloc(1000 * c->mc_lifetime * sizeof(int));
c->mc_charset = av_malloc(0x800 * sizeof(uint8_t));
avcodec_get_frame_defaults(&c->picture);
avctx->coded_frame = &c->picture;
@ -188,7 +211,7 @@ static int a64multi_encode_frame(AVCodecContext *avctx, unsigned char *buf,
if (req_size > buf_size) {
av_log(avctx, AV_LOG_ERROR, "buf size too small (need %d, got %d)\n", req_size, buf_size);
return -1;
return AVERROR(EINVAL);
}
/* fill up mc_meta_charset with framedata until lifetime exceeds */
if (c->mc_frame_counter < c->mc_lifetime) {
@ -203,8 +226,8 @@ static int a64multi_encode_frame(AVCodecContext *avctx, unsigned char *buf,
/* lifetime exceeded so now convert X frames at once */
if (c->mc_frame_counter == c->mc_lifetime && c->mc_lifetime > 0) {
c->mc_frame_counter = 0;
ff_init_elbg(meta, 32, 1000 * c-> mc_lifetime, best_cb, 256, 5, charmap, &c->randctx);
ff_do_elbg (meta, 32, 1000 * c-> mc_lifetime, best_cb, 256, 5, charmap, &c->randctx);
ff_init_elbg(meta, 32, 1000 * c-> mc_lifetime, best_cb, CHARSET_CHARS, 5, charmap, &c->randctx);
ff_do_elbg (meta, 32, 1000 * c-> mc_lifetime, best_cb, CHARSET_CHARS, 5, charmap, &c->randctx);
render_charset(avctx, buf, colrammap);
@ -223,7 +246,7 @@ static int a64multi_encode_frame(AVCodecContext *avctx, unsigned char *buf,
AVCodec a64multi_encoder = {
.name = "a64multi",
.type = CODEC_TYPE_VIDEO,
.type = AVMEDIA_TYPE_VIDEO,
.id = CODEC_ID_A64_MULTI,
.priv_data_size = sizeof(A64Context),
.init = a64multi_init_encoder,
@ -236,7 +259,7 @@ AVCodec a64multi_encoder = {
AVCodec a64multi5_encoder = {
.name = "a64multi5",
.type = CODEC_TYPE_VIDEO,
.type = AVMEDIA_TYPE_VIDEO,
.id = CODEC_ID_A64_MULTI5,
.priv_data_size = sizeof(A64Context),
.init = a64multi_init_encoder,

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@ -32,7 +32,8 @@
/**
* dither patterns used vor rendering the multicolor charset
*/
static const uint8_t prep_dither_patterns[9][4][4] = {
static const uint8_t multi_dither_patterns[9][4][4] = {
{
{0, 0, 0, 0},
{0, 0, 0, 0},

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@ -46,7 +46,7 @@ static int a64_write_header(struct AVFormatContext *s)
header[4] = 3;
break;
default:
return -1;
return AVERROR(EINVAL);
break;
}
put_buffer(s->pb, header, 2);