new file mode 100644

@@ -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 */

@@ -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 */

@@ -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,

@@ -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},

@@ -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);