X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fxsubdec.c;h=d9740c09fba23a677e84b8056c9916eb63c316d1;hb=39883fffa775b4d1593fd663e891d313fb577816;hp=d85e3226dead258b36f4de06c5dab736d52f0527;hpb=7e2643ae8d04ba6270b25c42f733ba5bfa76174a;p=ffmpeg

diff --git a/libavcodec/xsubdec.c b/libavcodec/xsubdec.c
index d85e3226dea..d9740c09fba 100644
--- a/libavcodec/xsubdec.c
+++ b/libavcodec/xsubdec.c
@@ -1,18 +1,52 @@
+/*
+ * XSUB subtitle decoder
+ * Copyright (c) 2007 Reimar Döffinger
+ *
+ * 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 "bitstream.h"
 #include "bytestream.h"
 
-static int decode_init(AVCodecContext *avctx) {
+static av_cold int decode_init(AVCodecContext *avctx) {
     avctx->pix_fmt = PIX_FMT_PAL8;
     return 0;
 }
 
-static const uint8_t runbits[8] = { 2, 2, 6, 6, 10, 10, 14, 14 };
+static const uint8_t tc_offsets[9] = { 0, 1, 3, 4, 6, 7, 9, 10, 11 };
+static const uint8_t tc_muls[9] = { 10, 6, 10, 6, 10, 6, 10, 10, 1 };
+
+static uint64_t parse_timecode(const uint8_t *buf) {
+    int i;
+    int64_t ms = 0;
+    if (buf[2] != ':' || buf[5] != ':' || buf[8] != '.')
+        return AV_NOPTS_VALUE;
+    for (i = 0; i < sizeof(tc_offsets); i++) {
+        uint8_t c = buf[tc_offsets[i]] - '0';
+        if (c > 9) return AV_NOPTS_VALUE;
+        ms = (ms + c) * tc_muls[i];
+    }
+    return ms;
+}
 
 static int decode_frame(AVCodecContext *avctx, void *data, int *data_size,
-                        uint8_t *buf, int buf_size) {
+                        const uint8_t *buf, int buf_size) {
     AVSubtitle *sub = data;
-    uint8_t *buf_end = buf + buf_size;
+    const uint8_t *buf_end = buf + buf_size;
     uint8_t *bitmap;
     int w, h, x, y, rlelen, i;
     GetBitContext gb;
@@ -23,6 +57,15 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size,
         return -1;
     }
 
+    // read start and end time
+    if (buf[0] != '[' || buf[13] != '-' || buf[26] != ']') {
+        av_log(avctx, AV_LOG_ERROR, "invalid time code\n");
+        return -1;
+    }
+    sub->start_display_time = parse_timecode(buf +  1);
+    sub->end_display_time   = parse_timecode(buf + 14);
+    buf += 27;
+
     // read header
     w = bytestream_get_le16(&buf);
     h = bytestream_get_le16(&buf);
@@ -40,7 +83,7 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size,
         sub->rects = av_mallocz(sizeof(AVSubtitleRect));
         sub->num_rects = 1;
     }
-    av_freep(sub->rects[0].bitmap);
+    av_freep(&sub->rects[0].bitmap);
     sub->rects[0].x = x; sub->rects[0].y = y;
     sub->rects[0].w = w; sub->rects[0].h = h;
     sub->rects[0].linesize = w;
@@ -51,23 +94,30 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size,
     // read palette
     for (i = 0; i < sub->rects[0].nb_colors; i++)
         sub->rects[0].rgba_palette[i] = bytestream_get_be24(&buf);
+    // make all except background (first entry) non-transparent
+    for (i = 1; i < sub->rects[0].nb_colors; i++)
+        sub->rects[0].rgba_palette[i] |= 0xff000000;
 
     // process RLE-compressed data
     rlelen = FFMIN(rlelen, buf_end - buf);
     init_get_bits(&gb, buf, rlelen * 8);
     bitmap = sub->rects[0].bitmap;
     for (y = 0; y < h; y++) {
+        // interlaced: do odd lines
+        if (y == (h + 1) / 2) bitmap = sub->rects[0].bitmap + w;
         for (x = 0; x < w; ) {
             int log2 = ff_log2_tab[show_bits(&gb, 8)];
-            int run = get_bits(&gb, runbits[log2]);
-            int colour = get_bits(&gb, 2);
+            int run = get_bits(&gb, 14 - 4 * (log2 >> 1));
+            int color = get_bits(&gb, 2);
             run = FFMIN(run, w - x);
             // run length 0 means till end of row
             if (!run) run = w - x;
-            memset(bitmap, colour, run);
+            memset(bitmap, color, run);
             bitmap += run;
             x += run;
         }
+        // interlaced, skip every second line
+        bitmap += w;
         align_get_bits(&gb);
     }
     *data_size = 1;
@@ -83,4 +133,5 @@ AVCodec xsub_decoder = {
     NULL,
     NULL,
     decode_frame,
+    .long_name = "XSUB",
 };