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authorTobias Bindhammer <tobias.bindhammer@uni-ulm.de>2010-08-23 11:46:32 +0000
committerTobias Bindhammer <tobias.bindhammer@uni-ulm.de>2010-08-23 11:46:32 +0000
commit7bf7833fb739fd436ca7fc98b30d6103f09931b1 (patch)
treec77c9986e76af752c6e615b15e08b44b9653f31c
parent620918e4bf69ad137b0a149c3a5fda501477eae0 (diff)
downloadffmpeg-7bf7833fb739fd436ca7fc98b30d6103f09931b1.tar.gz
Initial version of the a64 (multicolor charset) codec
Originally committed as revision 24873 to svn://svn.ffmpeg.org/ffmpeg/trunk
-rw-r--r--libavcodec/a64enc.h50
-rw-r--r--libavcodec/a64multienc.c248
-rw-r--r--libavcodec/a64tables.h92
3 files changed, 390 insertions, 0 deletions
diff --git a/libavcodec/a64enc.h b/libavcodec/a64enc.h
new file mode 100644
index 0000000000..3002f5001d
--- /dev/null
+++ b/libavcodec/a64enc.h
@@ -0,0 +1,50 @@
+/*
+ * a64 video encoder - basic headers
+ * 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 - basic headers
+ */
+
+#ifndef AVCODEC_A64ENC_H
+#define AVCODEC_A64ENC_H
+
+#include "libavutil/lfg.h"
+#include "avcodec.h"
+
+#define C64XRES 320
+#define C64YRES 200
+
+typedef struct A64Context {
+ /* general variables */
+ AVFrame picture;
+
+ /* variables for multicolor modes */
+ AVLFG randctx;
+ int mc_lifetime;
+ int mc_use_5col;
+ int mc_frame_counter;
+ int *mc_meta_charset;
+ int *mc_charmap;
+ int *mc_best_cb;
+} A64Context;
+
+#endif /* AVCODEC_A64ENC_H */
diff --git a/libavcodec/a64multienc.c b/libavcodec/a64multienc.c
new file mode 100644
index 0000000000..d2d0a1672a
--- /dev/null
+++ b/libavcodec/a64multienc.c
@@ -0,0 +1,248 @@
+/*
+ * a64 video encoder - multicolor modes
+ * 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 - multicolor modes
+ */
+
+#include "a64enc.h"
+#include "a64tables.h"
+#include "elbg.h"
+#include "libavutil/intreadwrite.h"
+
+#define DITHERSTEPS 8
+
+static void to_meta_with_crop(AVCodecContext *avctx, AVFrame *p, int *dest)
+{
+ int blockx, blocky, x, y;
+ int luma = 0;
+ int height = FFMIN(avctx->height,C64YRES);
+ int width = FFMIN(avctx->width ,C64XRES);
+ uint8_t *src = p->data[0];
+
+ for (blocky = 0; blocky < height; blocky += 8) {
+ for (blockx = 0; blockx < C64XRES; blockx += 8) {
+ for (y = blocky; y < blocky+8 && y < height; y++) {
+ for (x = blockx; x < blockx+8 && x < C64XRES; x += 2) {
+ if(x < width) {
+ /* build average over 2 pixels */
+ luma = (src[(x + 0 + y * p->linesize[0])] +
+ src[(x + 1 + y * p->linesize[0])]) / 2;
+ /* write blocks as linear data now so they are suitable for elbg */
+ dest[0] = luma;
+ }
+ dest++;
+ }
+ }
+ }
+ }
+}
+
+static void render_charset(AVCodecContext *avctx, uint8_t *charset,
+ uint8_t *colrammap)
+{
+ A64Context *c = avctx->priv_data;
+ uint8_t row1;
+ int charpos, x, y;
+ int pix;
+ int dither;
+ int index1, index2;
+ int lowdiff, highdiff;
+ int maxindex = c->mc_use_5col + 3;
+ int maxsteps = DITHERSTEPS * maxindex + 1;
+ int *best_cb = c->mc_best_cb;
+
+ /* now reduce colors first */
+ for (x = 0; x < 256 * 32; x++) best_cb[x] = best_cb[x] * maxsteps / 255;
+
+ /* and render charset */
+ for (charpos = 0; charpos < 256; 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;
+
+ 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 (lowdiff > highdiff) {
+ for (x = 0; x < 32; x++)
+ best_cb[x] = FFMIN(3 * DITHERSTEPS, best_cb[x]);
+ } else {
+ for (x = 0; x < 32; x++)
+ best_cb[x] = FFMAX(DITHERSTEPS, best_cb[x]);
+ }
+ charpos--; /* redo char */
+ } else {
+ /* advance pointers */
+ best_cb += 32;
+ charset += 8;
+
+ if (highdiff > 0) {
+ colrammap[charpos] = 0x9;
+ } else {
+ colrammap[charpos] = 0x8;
+ }
+ }
+ }
+}
+
+static av_cold int a64multi_close_encoder(AVCodecContext *avctx)
+{
+ A64Context *c = avctx->priv_data;
+ av_free(c->mc_meta_charset);
+ av_free(c->mc_best_cb);
+ av_free(c->mc_charmap);
+ return 0;
+}
+
+static av_cold int a64multi_init_encoder(AVCodecContext *avctx)
+{
+ A64Context *c = avctx->priv_data;
+ av_lfg_init(&c->randctx, 1);
+
+ if (avctx->global_quality < 1) {
+ c->mc_lifetime = 4;
+ } else {
+ c->mc_lifetime = avctx->global_quality /= FF_QP2LAMBDA;
+ }
+
+ av_log(avctx, AV_LOG_INFO, "charset lifetime set to %d frame(s)\n", c->mc_lifetime);
+
+ 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_charmap = av_malloc(1000 * c->mc_lifetime * sizeof(int));
+
+ avcodec_get_frame_defaults(&c->picture);
+ avctx->coded_frame = &c->picture;
+ avctx->coded_frame->pict_type = FF_I_TYPE;
+ avctx->coded_frame->key_frame = 1;
+ if (!avctx->codec_tag)
+ avctx->codec_tag = AV_RL32("a64m");
+
+ return 0;
+}
+
+static int a64multi_encode_frame(AVCodecContext *avctx, unsigned char *buf,
+ int buf_size, void *data)
+{
+ A64Context *c = avctx->priv_data;
+ AVFrame *pict = data;
+ AVFrame *const p = (AVFrame *) & c->picture;
+
+ int frame;
+ int a;
+
+ uint8_t colrammap[256];
+ int *charmap = c->mc_charmap;
+ int *meta = c->mc_meta_charset;
+ int *best_cb = c->mc_best_cb;
+ int frm_size = 0x400 + 0x400 * c->mc_use_5col;
+ int req_size;
+
+ /* it is the last frame so prepare to flush */
+ if (!data)
+ c->mc_lifetime = c->mc_frame_counter;
+
+ req_size = 0x800 + frm_size * c->mc_lifetime;
+
+ 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;
+ }
+ /* fill up mc_meta_charset with framedata until lifetime exceeds */
+ if (c->mc_frame_counter < c->mc_lifetime) {
+ *p = *pict;
+ p->pict_type = FF_I_TYPE;
+ p->key_frame = 1;
+ to_meta_with_crop(avctx, p, meta + 32000 * c->mc_frame_counter);
+ c->mc_frame_counter++;
+ /* lifetime is not reached */
+ return 0;
+ }
+ /* 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);
+
+ render_charset(avctx, buf, colrammap);
+
+ for (frame = 0; frame < c->mc_lifetime; frame++) {
+ for (a = 0; a < 1000; a++) {
+ buf[0x800 + a] = charmap[a];
+ if (c->mc_use_5col) buf[0xc00 + a] = colrammap[charmap[a]];
+ }
+ buf += frm_size;
+ charmap += 1000;
+ }
+ return req_size;
+ }
+ return 0;
+}
+
+AVCodec a64multi_encoder = {
+ .name = "a64multi",
+ .type = CODEC_TYPE_VIDEO,
+ .id = CODEC_ID_A64_MULTI,
+ .priv_data_size = sizeof(A64Context),
+ .init = a64multi_init_encoder,
+ .encode = a64multi_encode_frame,
+ .close = a64multi_close_encoder,
+ .pix_fmts = (enum PixelFormat[]) {PIX_FMT_GRAY8, PIX_FMT_NONE},
+ .long_name = NULL_IF_CONFIG_SMALL("Multicolor charset for Commodore 64"),
+ .capabilities = CODEC_CAP_DELAY,
+};
+
+AVCodec a64multi5_encoder = {
+ .name = "a64multi5",
+ .type = CODEC_TYPE_VIDEO,
+ .id = CODEC_ID_A64_MULTI5,
+ .priv_data_size = sizeof(A64Context),
+ .init = a64multi_init_encoder,
+ .encode = a64multi_encode_frame,
+ .close = a64multi_close_encoder,
+ .pix_fmts = (enum PixelFormat[]) {PIX_FMT_GRAY8, PIX_FMT_NONE},
+ .long_name = NULL_IF_CONFIG_SMALL("Multicolor charset for Commodore 64, extended with 5th color (colram)"),
+ .capabilities = CODEC_CAP_DELAY,
+};
diff --git a/libavcodec/a64tables.h b/libavcodec/a64tables.h
new file mode 100644
index 0000000000..31d8c2e2a0
--- /dev/null
+++ b/libavcodec/a64tables.h
@@ -0,0 +1,92 @@
+/*
+ * a64 video encoder - tables used by a64 encoders
+ * 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 - tables used by a64 encoders
+ */
+
+#ifndef AVCODEC_A64TABLES_H
+#define AVCODEC_A64TABLES_H
+
+#include <stdint.h>
+
+/**
+ * dither patterns used vor rendering the multicolor charset
+ */
+static const uint8_t prep_dither_patterns[9][4][4] = {
+ {
+ {0, 0, 0, 0},
+ {0, 0, 0, 0},
+ {0, 0, 0, 0},
+ {0, 0, 0, 0}
+ },
+ {
+ {1, 0, 0, 0},
+ {0, 0, 0, 0},
+ {0, 0, 1, 0},
+ {0, 0, 0, 0}
+ },
+ {
+ {1, 0, 0, 0},
+ {0, 0, 1, 0},
+ {0, 1, 0, 0},
+ {0, 0, 0, 1}
+ },
+ {
+ {1, 0, 0, 0},
+ {0, 1, 0, 1},
+ {0, 0, 1, 0},
+ {0, 1, 0, 1}
+ },
+ {
+ {1, 0, 1, 0},
+ {0, 1, 0, 1},
+ {1, 0, 1, 0},
+ {0, 1, 0, 1}
+ },
+ {
+ {1, 1, 1, 0},
+ {0, 1, 0, 1},
+ {1, 0, 1, 1},
+ {0, 1, 0, 1}
+ },
+ {
+ {0, 1, 1, 1},
+ {1, 1, 0, 1},
+ {1, 0, 1, 1},
+ {1, 1, 1, 0}
+ },
+ {
+ {0, 1, 1, 1},
+ {1, 1, 1, 1},
+ {1, 1, 0, 1},
+ {1, 1, 1, 1}
+ },
+ {
+ {1, 1, 1, 1},
+ {1, 1, 1, 1},
+ {1, 1, 1, 1},
+ {1, 1, 1, 1}
+ },
+};
+
+#endif /* AVCODEC_A64TABLES_H */