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authorTim Redfern <tim@eclectronics.org>2013-08-26 15:10:18 +0100
committerTim Redfern <tim@eclectronics.org>2013-08-26 15:10:18 +0100
commit150c9823e71a161e97003849cf8b2f55b21520bd (patch)
tree3559c840cf403d1386708b2591d58f928c7b160d /ffmpeg1/libavcodec/dvdsubenc.c
parentb4b1e2630c95d5e6014463f7608d59dc2322a3b8 (diff)
adding ffmpeg specific version
Diffstat (limited to 'ffmpeg1/libavcodec/dvdsubenc.c')
-rw-r--r--ffmpeg1/libavcodec/dvdsubenc.c443
1 files changed, 443 insertions, 0 deletions
diff --git a/ffmpeg1/libavcodec/dvdsubenc.c b/ffmpeg1/libavcodec/dvdsubenc.c
new file mode 100644
index 0000000..6e19623
--- /dev/null
+++ b/ffmpeg1/libavcodec/dvdsubenc.c
@@ -0,0 +1,443 @@
+/*
+ * DVD subtitle encoding
+ * Copyright (c) 2005 Wolfram Gloger
+ *
+ * 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
+ */
+#include "avcodec.h"
+#include "bytestream.h"
+#include "internal.h"
+#include "libavutil/avassert.h"
+#include "libavutil/bprint.h"
+#include "libavutil/imgutils.h"
+
+typedef struct {
+ uint32_t global_palette[16];
+} DVDSubtitleContext;
+
+// ncnt is the nibble counter
+#define PUTNIBBLE(val)\
+do {\
+ if (ncnt++ & 1)\
+ *q++ = bitbuf | ((val) & 0x0f);\
+ else\
+ bitbuf = (val) << 4;\
+} while(0)
+
+static void dvd_encode_rle(uint8_t **pq,
+ const uint8_t *bitmap, int linesize,
+ int w, int h,
+ const int cmap[256])
+{
+ uint8_t *q;
+ unsigned int bitbuf = 0;
+ int ncnt;
+ int x, y, len, color;
+
+ q = *pq;
+
+ for (y = 0; y < h; ++y) {
+ ncnt = 0;
+ for(x = 0; x < w; x += len) {
+ color = bitmap[x];
+ for (len=1; x+len < w; ++len)
+ if (bitmap[x+len] != color)
+ break;
+ color = cmap[color];
+ av_assert0(color < 4);
+ if (len < 0x04) {
+ PUTNIBBLE((len << 2)|color);
+ } else if (len < 0x10) {
+ PUTNIBBLE(len >> 2);
+ PUTNIBBLE((len << 2)|color);
+ } else if (len < 0x40) {
+ PUTNIBBLE(0);
+ PUTNIBBLE(len >> 2);
+ PUTNIBBLE((len << 2)|color);
+ } else if (x+len == w) {
+ PUTNIBBLE(0);
+ PUTNIBBLE(0);
+ PUTNIBBLE(0);
+ PUTNIBBLE(color);
+ } else {
+ if (len > 0xff)
+ len = 0xff;
+ PUTNIBBLE(0);
+ PUTNIBBLE(len >> 6);
+ PUTNIBBLE(len >> 2);
+ PUTNIBBLE((len << 2)|color);
+ }
+ }
+ /* end of line */
+ if (ncnt & 1)
+ PUTNIBBLE(0);
+ bitmap += linesize;
+ }
+
+ *pq = q;
+}
+
+static int color_distance(uint32_t a, uint32_t b)
+{
+ int r = 0, d, i;
+ int alpha_a = 8, alpha_b = 8;
+
+ for (i = 24; i >= 0; i -= 8) {
+ d = alpha_a * (int)((a >> i) & 0xFF) -
+ alpha_b * (int)((b >> i) & 0xFF);
+ r += d * d;
+ alpha_a = a >> 28;
+ alpha_b = b >> 28;
+ }
+ return r;
+}
+
+/**
+ * Count colors used in a rectangle, quantizing alpha and grouping by
+ * nearest global palette entry.
+ */
+static void count_colors(AVCodecContext *avctx, unsigned hits[33],
+ const AVSubtitleRect *r)
+{
+ DVDSubtitleContext *dvdc = avctx->priv_data;
+ unsigned count[256] = { 0 };
+ uint32_t *palette = (uint32_t *)r->pict.data[1];
+ uint32_t color;
+ int x, y, i, j, match, d, best_d, av_uninit(best_j);
+ uint8_t *p = r->pict.data[0];
+
+ for (y = 0; y < r->h; y++) {
+ for (x = 0; x < r->w; x++)
+ count[*(p++)]++;
+ p += r->pict.linesize[0] - r->w;
+ }
+ for (i = 0; i < 256; i++) {
+ if (!count[i]) /* avoid useless search */
+ continue;
+ color = palette[i];
+ /* 0: transparent, 1-16: semi-transparent, 17-33 opaque */
+ match = color < 0x33000000 ? 0 : color < 0xCC000000 ? 1 : 17;
+ if (match) {
+ best_d = INT_MAX;
+ for (j = 0; j < 16; j++) {
+ d = color_distance(0xFF000000 | color,
+ 0xFF000000 | dvdc->global_palette[j]);
+ if (d < best_d) {
+ best_d = d;
+ best_j = j;
+ }
+ }
+ match += best_j;
+ }
+ hits[match] += count[i];
+ }
+}
+
+static void select_palette(AVCodecContext *avctx, int out_palette[4],
+ int out_alpha[4], unsigned hits[33])
+{
+ DVDSubtitleContext *dvdc = avctx->priv_data;
+ int i, j, bright, mult;
+ uint32_t color;
+ int selected[4] = { 0 };
+ uint32_t pseudopal[33] = { 0 };
+ uint32_t refcolor[3] = { 0x00000000, 0xFFFFFFFF, 0xFF000000 };
+
+ /* Bonus for transparent: if the rectangle fits tightly the text, the
+ background color can be quite rare, but it would be ugly without it */
+ hits[0] *= 16;
+ /* Bonus for bright colors */
+ for (i = 0; i < 16; i++) {
+ if (!(hits[1 + i] + hits[17 + i]))
+ continue; /* skip unused colors to gain time */
+ color = dvdc->global_palette[i];
+ bright = 0;
+ for (j = 0; j < 3; j++, color >>= 8)
+ bright += (color & 0xFF) < 0x40 || (color & 0xFF) >= 0xC0;
+ mult = 2 + FFMIN(bright, 2);
+ hits[ 1 + i] *= mult;
+ hits[17 + i] *= mult;
+ }
+
+ /* Select four most frequent colors */
+ for (i = 0; i < 4; i++) {
+ for (j = 0; j < 33; j++)
+ if (hits[j] > hits[selected[i]])
+ selected[i] = j;
+ hits[selected[i]] = 0;
+ }
+
+ /* Order the colors like in most DVDs:
+ 0: background, 1: foreground, 2: outline */
+ for (i = 0; i < 16; i++) {
+ pseudopal[ 1 + i] = 0x80000000 | dvdc->global_palette[i];
+ pseudopal[17 + i] = 0xFF000000 | dvdc->global_palette[i];
+ }
+ for (i = 0; i < 3; i++) {
+ int best_d = color_distance(refcolor[i], pseudopal[selected[i]]);
+ for (j = i + 1; j < 4; j++) {
+ int d = color_distance(refcolor[i], pseudopal[selected[j]]);
+ if (d < best_d) {
+ FFSWAP(int, selected[i], selected[j]);
+ best_d = d;
+ }
+ }
+ }
+
+ /* Output */
+ for (i = 0; i < 4; i++) {
+ out_palette[i] = selected[i] ? (selected[i] - 1) & 0xF : 0;
+ out_alpha [i] = !selected[i] ? 0 : selected[i] < 17 ? 0x80 : 0xFF;
+ }
+}
+
+static void build_color_map(AVCodecContext *avctx, int cmap[],
+ const uint32_t palette[],
+ const int out_palette[], unsigned int const out_alpha[])
+{
+ DVDSubtitleContext *dvdc = avctx->priv_data;
+ int i, j, d, best_d;
+ uint32_t pseudopal[4];
+
+ for (i = 0; i < 4; i++)
+ pseudopal[i] = (out_alpha[i] << 24) |
+ dvdc->global_palette[out_palette[i]];
+ for (i = 0; i < 256; i++) {
+ best_d = INT_MAX;
+ for (j = 0; j < 4; j++) {
+ d = color_distance(pseudopal[j], palette[i]);
+ if (d < best_d) {
+ cmap[i] = j;
+ best_d = d;
+ }
+ }
+ }
+}
+
+static void copy_rectangle(AVSubtitleRect *dst, AVSubtitleRect *src, int cmap[])
+{
+ int x, y;
+ uint8_t *p, *q;
+
+ p = src->pict.data[0];
+ q = dst->pict.data[0] + (src->x - dst->x) +
+ (src->y - dst->y) * dst->pict.linesize[0];
+ for (y = 0; y < src->h; y++) {
+ for (x = 0; x < src->w; x++)
+ *(q++) = cmap[*(p++)];
+ p += src->pict.linesize[0] - src->w;
+ q += dst->pict.linesize[0] - src->w;
+ }
+}
+
+static int encode_dvd_subtitles(AVCodecContext *avctx,
+ uint8_t *outbuf, int outbuf_size,
+ const AVSubtitle *h)
+{
+ DVDSubtitleContext *dvdc = avctx->priv_data;
+ uint8_t *q, *qq;
+ int offset1, offset2;
+ int i, rects = h->num_rects, ret;
+ unsigned global_palette_hits[33] = { 0 };
+ int cmap[256];
+ int out_palette[4];
+ int out_alpha[4];
+ AVSubtitleRect vrect;
+ uint8_t *vrect_data = NULL;
+ int x2, y2;
+
+ if (rects == 0 || h->rects == NULL)
+ return AVERROR(EINVAL);
+ for (i = 0; i < rects; i++)
+ if (h->rects[i]->type != SUBTITLE_BITMAP) {
+ av_log(avctx, AV_LOG_ERROR, "Bitmap subtitle required\n");
+ return AVERROR(EINVAL);
+ }
+ vrect = *h->rects[0];
+
+ if (rects > 1) {
+ /* DVD subtitles can have only one rectangle: build a virtual
+ rectangle containing all actual rectangles.
+ The data of the rectangles will be copied later, when the palette
+ is decided, because the rectangles may have different palettes. */
+ int xmin = h->rects[0]->x, xmax = xmin + h->rects[0]->w;
+ int ymin = h->rects[0]->y, ymax = ymin + h->rects[0]->h;
+ for (i = 1; i < rects; i++) {
+ xmin = FFMIN(xmin, h->rects[i]->x);
+ ymin = FFMIN(ymin, h->rects[i]->y);
+ xmax = FFMAX(xmax, h->rects[i]->x + h->rects[i]->w);
+ ymax = FFMAX(ymax, h->rects[i]->y + h->rects[i]->h);
+ }
+ vrect.x = xmin;
+ vrect.y = ymin;
+ vrect.w = xmax - xmin;
+ vrect.h = ymax - ymin;
+ if ((ret = av_image_check_size(vrect.w, vrect.h, 0, avctx)) < 0)
+ return ret;
+
+ /* Count pixels outside the virtual rectangle as transparent */
+ global_palette_hits[0] = vrect.w * vrect.h;
+ for (i = 0; i < rects; i++)
+ global_palette_hits[0] -= h->rects[i]->w * h->rects[i]->h;
+ }
+
+ for (i = 0; i < rects; i++)
+ count_colors(avctx, global_palette_hits, h->rects[i]);
+ select_palette(avctx, out_palette, out_alpha, global_palette_hits);
+
+ if (rects > 1) {
+ if (!(vrect_data = av_calloc(vrect.w, vrect.h)))
+ return AVERROR(ENOMEM);
+ vrect.pict.data [0] = vrect_data;
+ vrect.pict.linesize[0] = vrect.w;
+ for (i = 0; i < rects; i++) {
+ build_color_map(avctx, cmap, (uint32_t *)h->rects[i]->pict.data[1],
+ out_palette, out_alpha);
+ copy_rectangle(&vrect, h->rects[i], cmap);
+ }
+ for (i = 0; i < 4; i++)
+ cmap[i] = i;
+ } else {
+ build_color_map(avctx, cmap, (uint32_t *)h->rects[0]->pict.data[1],
+ out_palette, out_alpha);
+ }
+
+ av_log(avctx, AV_LOG_DEBUG, "Selected palette:");
+ for (i = 0; i < 4; i++)
+ av_log(avctx, AV_LOG_DEBUG, " 0x%06x@@%02x (0x%x,0x%x)",
+ dvdc->global_palette[out_palette[i]], out_alpha[i],
+ out_palette[i], out_alpha[i] >> 4);
+ av_log(avctx, AV_LOG_DEBUG, "\n");
+
+ // encode data block
+ q = outbuf + 4;
+ offset1 = q - outbuf;
+ // worst case memory requirement: 1 nibble per pixel..
+ if ((q - outbuf) + vrect.w * vrect.h / 2 + 17 + 21 > outbuf_size) {
+ av_log(NULL, AV_LOG_ERROR, "dvd_subtitle too big\n");
+ ret = AVERROR_BUFFER_TOO_SMALL;
+ goto fail;
+ }
+ dvd_encode_rle(&q, vrect.pict.data[0], vrect.w * 2,
+ vrect.w, (vrect.h + 1) >> 1, cmap);
+ offset2 = q - outbuf;
+ dvd_encode_rle(&q, vrect.pict.data[0] + vrect.w, vrect.w * 2,
+ vrect.w, vrect.h >> 1, cmap);
+
+ // set data packet size
+ qq = outbuf + 2;
+ bytestream_put_be16(&qq, q - outbuf);
+
+ // send start display command
+ bytestream_put_be16(&q, (h->start_display_time*90) >> 10);
+ bytestream_put_be16(&q, (q - outbuf) /*- 2 */ + 8 + 12 + 2);
+ *q++ = 0x03; // palette - 4 nibbles
+ *q++ = (out_palette[3] << 4) | out_palette[2];
+ *q++ = (out_palette[1] << 4) | out_palette[0];
+ *q++ = 0x04; // alpha - 4 nibbles
+ *q++ = (out_alpha[3] & 0xF0) | (out_alpha[2] >> 4);
+ *q++ = (out_alpha[1] & 0xF0) | (out_alpha[0] >> 4);
+
+ // 12 bytes per rect
+ x2 = vrect.x + vrect.w - 1;
+ y2 = vrect.y + vrect.h - 1;
+
+ *q++ = 0x05;
+ // x1 x2 -> 6 nibbles
+ *q++ = vrect.x >> 4;
+ *q++ = (vrect.x << 4) | ((x2 >> 8) & 0xf);
+ *q++ = x2;
+ // y1 y2 -> 6 nibbles
+ *q++ = vrect.y >> 4;
+ *q++ = (vrect.y << 4) | ((y2 >> 8) & 0xf);
+ *q++ = y2;
+
+ *q++ = 0x06;
+ // offset1, offset2
+ bytestream_put_be16(&q, offset1);
+ bytestream_put_be16(&q, offset2);
+
+ *q++ = 0x01; // start command
+ *q++ = 0xff; // terminating command
+
+ // send stop display command last
+ bytestream_put_be16(&q, (h->end_display_time*90) >> 10);
+ bytestream_put_be16(&q, (q - outbuf) - 2 /*+ 4*/);
+ *q++ = 0x02; // set end
+ *q++ = 0xff; // terminating command
+
+ qq = outbuf;
+ bytestream_put_be16(&qq, q - outbuf);
+
+ av_log(NULL, AV_LOG_DEBUG, "subtitle_packet size=%td\n", q - outbuf);
+ ret = q - outbuf;
+
+fail:
+ av_free(vrect_data);
+ return ret;
+}
+
+static int dvdsub_init(AVCodecContext *avctx)
+{
+ DVDSubtitleContext *dvdc = avctx->priv_data;
+ static const uint32_t default_palette[16] = {
+ 0x000000, 0x0000FF, 0x00FF00, 0xFF0000,
+ 0xFFFF00, 0xFF00FF, 0x00FFFF, 0xFFFFFF,
+ 0x808000, 0x8080FF, 0x800080, 0x80FF80,
+ 0x008080, 0xFF8080, 0x555555, 0xAAAAAA,
+ };
+ AVBPrint extradata;
+ int i, ret;
+
+ av_assert0(sizeof(dvdc->global_palette) == sizeof(default_palette));
+ memcpy(dvdc->global_palette, default_palette, sizeof(dvdc->global_palette));
+
+ av_bprint_init(&extradata, 0, 1);
+ if (avctx->width && avctx->height)
+ av_bprintf(&extradata, "size: %dx%d\n", avctx->width, avctx->height);
+ av_bprintf(&extradata, "palette:");
+ for (i = 0; i < 16; i++)
+ av_bprintf(&extradata, " %06"PRIx32"%c",
+ dvdc->global_palette[i] & 0xFFFFFF, i < 15 ? ',' : '\n');
+
+ ret = avpriv_bprint_to_extradata(avctx, &extradata);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int dvdsub_encode(AVCodecContext *avctx,
+ unsigned char *buf, int buf_size,
+ const AVSubtitle *sub)
+{
+ //DVDSubtitleContext *s = avctx->priv_data;
+ int ret;
+
+ ret = encode_dvd_subtitles(avctx, buf, buf_size, sub);
+ return ret;
+}
+
+AVCodec ff_dvdsub_encoder = {
+ .name = "dvdsub",
+ .type = AVMEDIA_TYPE_SUBTITLE,
+ .id = AV_CODEC_ID_DVD_SUBTITLE,
+ .init = dvdsub_init,
+ .encode_sub = dvdsub_encode,
+ .long_name = NULL_IF_CONFIG_SMALL("DVD subtitles"),
+ .priv_data_size = sizeof(DVDSubtitleContext),
+};