avcodec/aacdec_fixed: fix invalid shift in predict()
[ffmpeg.git] / libavcodec / dvdsubdec.c
index bb28d9e..e18113c 100644 (file)
 #include "libavutil/opt.h"
 #include "libavutil/imgutils.h"
 #include "libavutil/avstring.h"
+#include "libavutil/bswap.h"
 
 typedef struct DVDSubContext
 {
   AVClass *class;
   uint32_t palette[16];
   char    *palette_str;
+  char    *ifo_str;
   int      has_palette;
   uint8_t  colormap[4];
   uint8_t  alpha[256];
-  uint8_t *buf;
+  uint8_t  buf[0x10000];
   int      buf_size;
   int      forced_subs_only;
 #ifdef DEBUG
@@ -58,7 +60,7 @@ static void yuv_a_to_rgba(const uint8_t *ycbcr, const uint8_t *alpha, uint32_t *
         cb = *ycbcr++;
         YUV_TO_RGB1_CCIR(cb, cr);
         YUV_TO_RGB2_CCIR(r, g, b, y);
-        *rgba++ = (*alpha++ << 24) | (r << 16) | (g << 8) | b;
+        *rgba++ = ((unsigned)*alpha++ << 24) | (r << 16) | (g << 8) | b;
     }
 }
 
@@ -106,6 +108,12 @@ static int decode_rle(uint8_t *bitmap, int linesize, int w, int h,
     int x, y, len, color;
     uint8_t *d;
 
+    if (start >= buf_size)
+        return -1;
+
+    if (w <= 0 || h <= 0)
+        return -1;
+
     bit_len = (buf_size - start) * 8;
     init_get_bits(&gb, buf + start, bit_len);
 
@@ -177,16 +185,16 @@ static void guess_palette(DVDSubContext* ctx,
     for(i = 0; i < 4; i++) {
         if (alpha[i] != 0) {
             if (!color_used[colormap[i]])  {
-                level = level_map[nb_opaque_colors][j];
+                level = level_map[nb_opaque_colors - 1][j];
                 r = (((subtitle_color >> 16) & 0xff) * level) >> 8;
                 g = (((subtitle_color >> 8) & 0xff) * level) >> 8;
                 b = (((subtitle_color >> 0) & 0xff) * level) >> 8;
-                rgba_palette[i] = b | (g << 8) | (r << 16) | ((alpha[i] * 17) << 24);
+                rgba_palette[i] = b | (g << 8) | (r << 16) | ((alpha[i] * 17U) << 24);
                 color_used[colormap[i]] = (i + 1);
                 j++;
             } else {
                 rgba_palette[i] = (rgba_palette[color_used[colormap[i]] - 1] & 0x00ffffff) |
-                                    ((alpha[i] * 17) << 24);
+                                    ((alpha[i] * 17U) << 24);
             }
         }
     }
@@ -198,8 +206,8 @@ static void reset_rects(AVSubtitle *sub_header)
 
     if (sub_header->rects) {
         for (i = 0; i < sub_header->num_rects; i++) {
-            av_freep(&sub_header->rects[i]->pict.data[0]);
-            av_freep(&sub_header->rects[i]->pict.data[1]);
+            av_freep(&sub_header->rects[i]->data[0]);
+            av_freep(&sub_header->rects[i]->data[1]);
             av_freep(&sub_header->rects[i]);
         }
         av_freep(&sub_header->rects);
@@ -212,13 +220,15 @@ static void reset_rects(AVSubtitle *sub_header)
 static int decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header,
                                 const uint8_t *buf, int buf_size)
 {
-    int cmd_pos, pos, cmd, x1, y1, x2, y2, offset1, offset2, next_cmd_pos;
+    int cmd_pos, pos, cmd, x1, y1, x2, y2, next_cmd_pos;
     int big_offsets, offset_size, is_8bit = 0;
     const uint8_t *yuv_palette = NULL;
     uint8_t *colormap = ctx->colormap, *alpha = ctx->alpha;
     int date;
     int i;
     int is_menu = 0;
+    uint32_t size;
+    int64_t offset1, offset2;
 
     if (buf_size < 10)
         return -1;
@@ -233,15 +243,21 @@ static int decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header,
         cmd_pos = 2;
     }
 
+    size = READ_OFFSET(buf + (big_offsets ? 2 : 0));
     cmd_pos = READ_OFFSET(buf + cmd_pos);
 
-    if (cmd_pos < 0 || cmd_pos > buf_size - 2 - offset_size)
+    if (cmd_pos < 0 || cmd_pos > buf_size - 2 - offset_size) {
+        if (cmd_pos > size) {
+            av_log(ctx, AV_LOG_ERROR, "Discarding invalid packet\n");
+            return 0;
+        }
         return AVERROR(EAGAIN);
+    }
 
     while (cmd_pos > 0 && cmd_pos < buf_size - 2 - offset_size) {
         date = AV_RB16(buf + cmd_pos);
         next_cmd_pos = READ_OFFSET(buf + cmd_pos + 2);
-        av_dlog(NULL, "cmd_pos=0x%04x next=0x%04x date=%d\n",
+        ff_dlog(NULL, "cmd_pos=0x%04x next=0x%04x date=%d\n",
                 cmd_pos, next_cmd_pos, date);
         pos = cmd_pos + 2 + offset_size;
         offset1 = -1;
@@ -249,7 +265,7 @@ static int decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header,
         x1 = y1 = x2 = y2 = 0;
         while (pos < buf_size) {
             cmd = buf[pos++];
-            av_dlog(NULL, "cmd=%02x\n", cmd);
+            ff_dlog(NULL, "cmd=%02x\n", cmd);
             switch(cmd) {
             case 0x00:
                 /* menu subpicture */
@@ -282,7 +298,7 @@ static int decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header,
                 alpha[1] = buf[pos + 1] >> 4;
                 alpha[0] = buf[pos + 1] & 0x0f;
                 pos += 2;
-            av_dlog(NULL, "alpha=%x%x%x%x\n", alpha[0],alpha[1],alpha[2],alpha[3]);
+                ff_dlog(NULL, "alpha=%x%x%x%x\n", alpha[0],alpha[1],alpha[2],alpha[3]);
                 break;
             case 0x05:
             case 0x85:
@@ -294,7 +310,7 @@ static int decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header,
                 y2 = ((buf[pos + 4] & 0x0f) << 8) | buf[pos + 5];
                 if (cmd & 0x80)
                     is_8bit = 1;
-                av_dlog(NULL, "x1=%d x2=%d y1=%d y2=%d\n", x1, x2, y1, y2);
+                ff_dlog(NULL, "x1=%d x2=%d y1=%d y2=%d\n", x1, x2, y1, y2);
                 pos += 6;
                 break;
             case 0x06:
@@ -302,7 +318,7 @@ static int decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header,
                     goto fail;
                 offset1 = AV_RB16(buf + pos);
                 offset2 = AV_RB16(buf + pos + 2);
-                av_dlog(NULL, "offset1=0x%04x offset2=0x%04x\n", offset1, offset2);
+                ff_dlog(NULL, "offset1=0x%04"PRIx64" offset2=0x%04"PRIx64"\n", offset1, offset2);
                 pos += 4;
                 break;
             case 0x86:
@@ -310,7 +326,7 @@ static int decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header,
                     goto fail;
                 offset1 = AV_RB32(buf + pos);
                 offset2 = AV_RB32(buf + pos + 4);
-                av_dlog(NULL, "offset1=0x%04x offset2=0x%04x\n", offset1, offset2);
+                ff_dlog(NULL, "offset1=0x%04"PRIx64" offset2=0x%04"PRIx64"\n", offset1, offset2);
                 pos += 8;
                 break;
 
@@ -333,12 +349,15 @@ static int decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header,
             case 0xff:
                 goto the_end;
             default:
-                av_dlog(NULL, "unrecognised subpicture command 0x%x\n", cmd);
+                ff_dlog(NULL, "unrecognised subpicture command 0x%x\n", cmd);
                 goto the_end;
             }
         }
     the_end:
-        if (offset1 >= 0) {
+        if (offset1 >= buf_size || offset2 >= buf_size)
+            goto fail;
+
+        if (offset1 >= 0 && offset2 >= 0) {
             int w, h;
             uint8_t *bitmap;
 
@@ -349,27 +368,38 @@ static int decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header,
             h = y2 - y1 + 1;
             if (h < 0)
                 h = 0;
-            if (w > 0 && h > 0) {
+            if (w > 0 && h > 1) {
                 reset_rects(sub_header);
 
-                bitmap = av_malloc(w * h);
                 sub_header->rects = av_mallocz(sizeof(*sub_header->rects));
+                if (!sub_header->rects)
+                    goto fail;
                 sub_header->rects[0] = av_mallocz(sizeof(AVSubtitleRect));
+                if (!sub_header->rects[0])
+                    goto fail;
                 sub_header->num_rects = 1;
-                sub_header->rects[0]->pict.data[0] = bitmap;
-                decode_rle(bitmap, w * 2, w, (h + 1) / 2,
-                           buf, offset1, buf_size, is_8bit);
-                decode_rle(bitmap + w, w * 2, w, h / 2,
-                           buf, offset2, buf_size, is_8bit);
-                sub_header->rects[0]->pict.data[1] = av_mallocz(AVPALETTE_SIZE);
+                bitmap = sub_header->rects[0]->data[0] = av_malloc(w * h);
+                if (!bitmap)
+                    goto fail;
+                if (decode_rle(bitmap, w * 2, w, (h + 1) / 2,
+                               buf, offset1, buf_size, is_8bit) < 0)
+                    goto fail;
+                if (decode_rle(bitmap + w, w * 2, w, h / 2,
+                               buf, offset2, buf_size, is_8bit) < 0)
+                    goto fail;
+                sub_header->rects[0]->data[1] = av_mallocz(AVPALETTE_SIZE);
+                if (!sub_header->rects[0]->data[1])
+                    goto fail;
                 if (is_8bit) {
                     if (!yuv_palette)
                         goto fail;
                     sub_header->rects[0]->nb_colors = 256;
-                    yuv_a_to_rgba(yuv_palette, alpha, (uint32_t*)sub_header->rects[0]->pict.data[1], 256);
+                    yuv_a_to_rgba(yuv_palette, alpha,
+                                  (uint32_t *)sub_header->rects[0]->data[1],
+                                  256);
                 } else {
                     sub_header->rects[0]->nb_colors = 4;
-                    guess_palette(ctx, (uint32_t*)sub_header->rects[0]->pict.data[1],
+                    guess_palette(ctx, (uint32_t*)sub_header->rects[0]->data[1],
                                   0xffff00);
                 }
                 sub_header->rects[0]->x = x1;
@@ -377,12 +407,21 @@ static int decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header,
                 sub_header->rects[0]->w = w;
                 sub_header->rects[0]->h = h;
                 sub_header->rects[0]->type = SUBTITLE_BITMAP;
-                sub_header->rects[0]->pict.linesize[0] = w;
+                sub_header->rects[0]->linesize[0] = w;
                 sub_header->rects[0]->flags = is_menu ? AV_SUBTITLE_FLAG_FORCED : 0;
+
+#if FF_API_AVPICTURE
+FF_DISABLE_DEPRECATION_WARNINGS
+                for (i = 0; i < 4; i++) {
+                    sub_header->rects[0]->pict.data[i] = sub_header->rects[0]->data[i];
+                    sub_header->rects[0]->pict.linesize[i] = sub_header->rects[0]->linesize[i];
+                }
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
             }
         }
         if (next_cmd_pos < cmd_pos) {
-            av_log(NULL, AV_LOG_ERROR, "Invalid command offset\n");
+            av_log(ctx, AV_LOG_ERROR, "Invalid command offset\n");
             break;
         }
         if (next_cmd_pos == cmd_pos)
@@ -419,29 +458,29 @@ static int find_smallest_bounding_rectangle(AVSubtitle *s)
         return 0;
 
     for(i = 0; i < s->rects[0]->nb_colors; i++) {
-        if ((((uint32_t*)s->rects[0]->pict.data[1])[i] >> 24) == 0)
+        if ((((uint32_t *)s->rects[0]->data[1])[i] >> 24) == 0)
             transp_color[i] = 1;
     }
     y1 = 0;
-    while (y1 < s->rects[0]->h && is_transp(s->rects[0]->pict.data[0] + y1 * s->rects[0]->pict.linesize[0],
+    while (y1 < s->rects[0]->h && is_transp(s->rects[0]->data[0] + y1 * s->rects[0]->linesize[0],
                                   1, s->rects[0]->w, transp_color))
         y1++;
     if (y1 == s->rects[0]->h) {
-        av_freep(&s->rects[0]->pict.data[0]);
+        av_freep(&s->rects[0]->data[0]);
         s->rects[0]->w = s->rects[0]->h = 0;
         return 0;
     }
 
     y2 = s->rects[0]->h - 1;
-    while (y2 > 0 && is_transp(s->rects[0]->pict.data[0] + y2 * s->rects[0]->pict.linesize[0], 1,
+    while (y2 > 0 && is_transp(s->rects[0]->data[0] + y2 * s->rects[0]->linesize[0], 1,
                                s->rects[0]->w, transp_color))
         y2--;
     x1 = 0;
-    while (x1 < (s->rects[0]->w - 1) && is_transp(s->rects[0]->pict.data[0] + x1, s->rects[0]->pict.linesize[0],
+    while (x1 < (s->rects[0]->w - 1) && is_transp(s->rects[0]->data[0] + x1, s->rects[0]->linesize[0],
                                         s->rects[0]->h, transp_color))
         x1++;
     x2 = s->rects[0]->w - 1;
-    while (x2 > 0 && is_transp(s->rects[0]->pict.data[0] + x2, s->rects[0]->pict.linesize[0], s->rects[0]->h,
+    while (x2 > 0 && is_transp(s->rects[0]->data[0] + x2, s->rects[0]->linesize[0], s->rects[0]->h,
                                   transp_color))
         x2--;
     w = x2 - x1 + 1;
@@ -450,15 +489,25 @@ static int find_smallest_bounding_rectangle(AVSubtitle *s)
     if (!bitmap)
         return 1;
     for(y = 0; y < h; y++) {
-        memcpy(bitmap + w * y, s->rects[0]->pict.data[0] + x1 + (y1 + y) * s->rects[0]->pict.linesize[0], w);
+        memcpy(bitmap + w * y, s->rects[0]->data[0] + x1 + (y1 + y) * s->rects[0]->linesize[0], w);
     }
-    av_freep(&s->rects[0]->pict.data[0]);
-    s->rects[0]->pict.data[0] = bitmap;
-    s->rects[0]->pict.linesize[0] = w;
+    av_freep(&s->rects[0]->data[0]);
+    s->rects[0]->data[0] = bitmap;
+    s->rects[0]->linesize[0] = w;
     s->rects[0]->w = w;
     s->rects[0]->h = h;
     s->rects[0]->x += x1;
     s->rects[0]->y += y1;
+
+#if FF_API_AVPICTURE
+FF_DISABLE_DEPRECATION_WARNINGS
+    for (i = 0; i < 4; i++) {
+        s->rects[0]->pict.data[i] = s->rects[0]->data[i];
+        s->rects[0]->pict.linesize[i] = s->rects[0]->linesize[i];
+    }
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
+
     return 1;
 }
 
@@ -499,15 +548,13 @@ static int append_to_cached_buf(AVCodecContext *avctx,
 {
     DVDSubContext *ctx = avctx->priv_data;
 
-    if (ctx->buf_size > 0xffff - buf_size) {
+    av_assert0(buf_size >= 0 && ctx->buf_size <= sizeof(ctx->buf));
+    if (buf_size >= sizeof(ctx->buf) - ctx->buf_size) {
         av_log(avctx, AV_LOG_WARNING, "Attempt to reconstruct "
                "too large SPU packets aborted.\n");
-        av_freep(&ctx->buf);
+        ctx->buf_size = 0;
         return AVERROR_INVALIDDATA;
     }
-    ctx->buf = av_realloc(ctx->buf, ctx->buf_size + buf_size);
-    if (!ctx->buf)
-        return AVERROR(ENOMEM);
     memcpy(ctx->buf + ctx->buf_size, buf, buf_size);
     ctx->buf_size += buf_size;
     return 0;
@@ -521,9 +568,10 @@ static int dvdsub_decode(AVCodecContext *avctx,
     const uint8_t *buf = avpkt->data;
     int buf_size = avpkt->size;
     AVSubtitle *sub = data;
+    int appended = 0;
     int is_menu;
 
-    if (ctx->buf) {
+    if (ctx->buf_size) {
         int ret = append_to_cached_buf(avctx, buf, buf_size);
         if (ret < 0) {
             *data_size = 0;
@@ -531,12 +579,13 @@ static int dvdsub_decode(AVCodecContext *avctx,
         }
         buf = ctx->buf;
         buf_size = ctx->buf_size;
+        appended = 1;
     }
 
     is_menu = decode_dvd_subtitles(ctx, sub, buf, buf_size);
     if (is_menu == AVERROR(EAGAIN)) {
         *data_size = 0;
-        return append_to_cached_buf(avctx, buf, buf_size);
+        return appended ? 0 : append_to_cached_buf(avctx, buf, buf_size);
     }
 
     if (is_menu < 0) {
@@ -557,15 +606,14 @@ static int dvdsub_decode(AVCodecContext *avctx,
     char ppm_name[32];
 
     snprintf(ppm_name, sizeof(ppm_name), "/tmp/%05d.ppm", ctx->sub_id++);
-    av_dlog(NULL, "start=%d ms end =%d ms\n",
+    ff_dlog(NULL, "start=%d ms end =%d ms\n",
             sub->start_display_time,
             sub->end_display_time);
-    ppm_save(ppm_name, sub->rects[0]->pict.data[0],
-             sub->rects[0]->w, sub->rects[0]->h, (uint32_t*) sub->rects[0]->pict.data[1]);
+    ppm_save(ppm_name, sub->rects[0]->data[0],
+             sub->rects[0]->w, sub->rects[0]->h, (uint32_t*) sub->rects[0]->data[1]);
     }
 #endif
 
-    av_freep(&ctx->buf);
     ctx->buf_size = 0;
     *data_size = 1;
     return buf_size;
@@ -583,10 +631,71 @@ static void parse_palette(DVDSubContext *ctx, char *p)
     }
 }
 
+static int parse_ifo_palette(DVDSubContext *ctx, char *p)
+{
+    FILE *ifo;
+    char ifostr[12];
+    uint32_t sp_pgci, pgci, off_pgc, pgc;
+    uint8_t r, g, b, yuv[65], *buf;
+    int i, y, cb, cr, r_add, g_add, b_add;
+    int ret = 0;
+    const uint8_t *cm = ff_crop_tab + MAX_NEG_CROP;
+
+    ctx->has_palette = 0;
+    if ((ifo = fopen(p, "r")) == NULL) {
+        av_log(ctx, AV_LOG_WARNING, "Unable to open IFO file \"%s\": %s\n", p, av_err2str(AVERROR(errno)));
+        return AVERROR_EOF;
+    }
+    if (fread(ifostr, 12, 1, ifo) != 1 || memcmp(ifostr, "DVDVIDEO-VTS", 12)) {
+        av_log(ctx, AV_LOG_WARNING, "\"%s\" is not a proper IFO file\n", p);
+        ret = AVERROR_INVALIDDATA;
+        goto end;
+    }
+    if (fseek(ifo, 0xCC, SEEK_SET) == -1) {
+        ret = AVERROR(errno);
+        goto end;
+    }
+    if (fread(&sp_pgci, 4, 1, ifo) == 1) {
+        pgci = av_be2ne32(sp_pgci) * 2048;
+        if (fseek(ifo, pgci + 0x0C, SEEK_SET) == -1) {
+            ret = AVERROR(errno);
+            goto end;
+        }
+        if (fread(&off_pgc, 4, 1, ifo) == 1) {
+            pgc = pgci + av_be2ne32(off_pgc);
+            if (fseek(ifo, pgc + 0xA4, SEEK_SET) == -1) {
+                ret = AVERROR(errno);
+                goto end;
+            }
+            if (fread(yuv, 64, 1, ifo) == 1) {
+                buf = yuv;
+                for(i=0; i<16; i++) {
+                    y  = *++buf;
+                    cr = *++buf;
+                    cb = *++buf;
+                    YUV_TO_RGB1_CCIR(cb, cr);
+                    YUV_TO_RGB2_CCIR(r, g, b, y);
+                    ctx->palette[i] = (r << 16) + (g << 8) + b;
+                    buf++;
+                }
+                ctx->has_palette = 1;
+            }
+        }
+    }
+    if (ctx->has_palette == 0) {
+        av_log(ctx, AV_LOG_WARNING, "Failed to read palette from IFO file \"%s\"\n", p);
+        ret = AVERROR_INVALIDDATA;
+    }
+end:
+    fclose(ifo);
+    return ret;
+}
+
 static int dvdsub_parse_extradata(AVCodecContext *avctx)
 {
     DVDSubContext *ctx = (DVDSubContext*) avctx->priv_data;
     char *dataorig, *data;
+    int ret = 1;
 
     if (!avctx->extradata || !avctx->extradata_size)
         return 1;
@@ -607,11 +716,9 @@ static int dvdsub_parse_extradata(AVCodecContext *avctx)
         } else if (strncmp("size:", data, 5) == 0) {
             int w, h;
             if (sscanf(data + 5, "%dx%d", &w, &h) == 2) {
-               int ret = ff_set_dimensions(avctx, w, h);
-               if (ret < 0) {
-                   av_free(dataorig);
-                   return ret;
-               }
+               ret = ff_set_dimensions(avctx, w, h);
+               if (ret < 0)
+                   goto fail;
             }
         }
 
@@ -619,8 +726,9 @@ static int dvdsub_parse_extradata(AVCodecContext *avctx)
         data += strspn(data, "\n\r");
     }
 
+fail:
     av_free(dataorig);
-    return 1;
+    return ret;
 }
 
 static av_cold int dvdsub_init(AVCodecContext *avctx)
@@ -631,24 +739,30 @@ static av_cold int dvdsub_init(AVCodecContext *avctx)
     if ((ret = dvdsub_parse_extradata(avctx)) < 0)
         return ret;
 
+    if (ctx->ifo_str)
+        parse_ifo_palette(ctx, ctx->ifo_str);
     if (ctx->palette_str)
         parse_palette(ctx, ctx->palette_str);
     if (ctx->has_palette) {
         int i;
         av_log(avctx, AV_LOG_DEBUG, "palette:");
         for(i=0;i<16;i++)
-            av_log(avctx, AV_LOG_DEBUG, " 0x%06x", ctx->palette[i]);
+            av_log(avctx, AV_LOG_DEBUG, " 0x%06"PRIx32, ctx->palette[i]);
         av_log(avctx, AV_LOG_DEBUG, "\n");
     }
 
     return 1;
 }
 
-static av_cold int dvdsub_close(AVCodecContext *avctx)
+static void dvdsub_flush(AVCodecContext *avctx)
 {
     DVDSubContext *ctx = avctx->priv_data;
-    av_freep(&ctx->buf);
     ctx->buf_size = 0;
+}
+
+static av_cold int dvdsub_close(AVCodecContext *avctx)
+{
+    dvdsub_flush(avctx);
     return 0;
 }
 
@@ -656,7 +770,8 @@ static av_cold int dvdsub_close(AVCodecContext *avctx)
 #define SD AV_OPT_FLAG_SUBTITLE_PARAM | AV_OPT_FLAG_DECODING_PARAM
 static const AVOption options[] = {
     { "palette", "set the global palette", OFFSET(palette_str), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, SD },
-    { "forced_subs_only", "Only show forced subtitles", OFFSET(forced_subs_only), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, SD},
+    { "ifo_palette", "obtain the global palette from .IFO file", OFFSET(ifo_str), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, SD },
+    { "forced_subs_only", "Only show forced subtitles", OFFSET(forced_subs_only), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, SD},
     { NULL }
 };
 static const AVClass dvdsub_class = {
@@ -674,6 +789,7 @@ AVCodec ff_dvdsub_decoder = {
     .priv_data_size = sizeof(DVDSubContext),
     .init           = dvdsub_init,
     .decode         = dvdsub_decode,
+    .flush          = dvdsub_flush,
     .close          = dvdsub_close,
     .priv_class     = &dvdsub_class,
 };