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authorTobias Bindhammer <tobias.bindhammer@uni-ulm.de>2010-08-24 14:02:31 +0000
committerTobias Bindhammer <tobias.bindhammer@uni-ulm.de>2010-08-24 14:02:31 +0000
commitbb07ab7cf22e7bf0717264f9e7b15dfb6d67e391 (patch)
tree6e616819f4c2fe973de9e632896d3c31e4794822 /libavcodec/a64multienc.c
parentac9c19da66b54e690f17001e7eb855bae5f23d0d (diff)
downloadffmpeg-bb07ab7cf22e7bf0717264f9e7b15dfb6d67e391.tar.gz
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
Diffstat (limited to 'libavcodec/a64multienc.c')
-rw-r--r--libavcodec/a64multienc.c103
1 files changed, 63 insertions, 40 deletions
diff --git a/libavcodec/a64multienc.c b/libavcodec/a64multienc.c
index d2d0a1672a..ec2af9954b 100644
--- a/libavcodec/a64multienc.c
+++ b/libavcodec/a64multienc.c
@@ -25,11 +25,16 @@
*/
#include "a64enc.h"
+#include "a64colors.h"
#include "a64tables.h"
#include "elbg.h"
#include "libavutil/intreadwrite.h"
-#define DITHERSTEPS 8
+#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);
- }
+
+ if (multi_dither_patterns[dither[pix]][(y & 3)][x & 3])
+ row1 |= 3-(index2[pix] & 3);
+ else
+ row1 |= 3-(index1[pix] & 3);
}
- charset[y] = row1;
+ charset[y+0x000] = row1;
}
-
- /* are we in 5col mode and need to adjust pixels? */
- if (c->mc_use_5col && highdiff > 0 && lowdiff > 0) {
+ /* 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,