X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fdvbsubdec.c;h=1d62b8ad4235443b357df387c8dca5b3da5e1c45;hb=607ad990d31e6be52980970e5ce8cd25ab3de812;hp=689c06883356e205408e24cf48686500ba22b9ad;hpb=25b4c651a3de58ea14c59131c650593736004686;p=ffmpeg

diff --git a/libavcodec/dvbsubdec.c b/libavcodec/dvbsubdec.c
index 689c0688335..1d62b8ad423 100644
--- a/libavcodec/dvbsubdec.c
+++ b/libavcodec/dvbsubdec.c
@@ -1,42 +1,39 @@
 /*
- * DVB subtitle decoding for ffmpeg
- * Copyright (c) 2005 Ian Caulfield.
+ * DVB subtitle decoding
+ * Copyright (c) 2005 Ian Caulfield
  *
- * This file is part of FFmpeg.
+ * This file is part of Libav.
  *
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav 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,
+ * Libav 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
+ * License along with Libav; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
-#include "avcodec.h"
-#include "dsputil.h"
-#include "bitstream.h"
-#include "colorspace.h"
 
-//#define DEBUG
-//#define DEBUG_PACKET_CONTENTS
-//#define DEBUG_SAVE_IMAGES
+#include "avcodec.h"
+#include "get_bits.h"
+#include "bytestream.h"
+#include "libavutil/colorspace.h"
 
 #define DVBSUB_PAGE_SEGMENT     0x10
 #define DVBSUB_REGION_SEGMENT   0x11
 #define DVBSUB_CLUT_SEGMENT     0x12
 #define DVBSUB_OBJECT_SEGMENT   0x13
+#define DVBSUB_DISPLAYDEFINITION_SEGMENT 0x14
 #define DVBSUB_DISPLAY_SEGMENT  0x80
 
-#define cm (ff_cropTbl + MAX_NEG_CROP)
+#define cm (ff_crop_tab + MAX_NEG_CROP)
 
-#ifdef DEBUG_SAVE_IMAGES
-#undef fprintf
+#ifdef DEBUG
 #if 0
 static void png_save(const char *filename, uint8_t *bitmap, int w, int h,
                      uint32_t *rgba_palette)
@@ -51,7 +48,7 @@ static void png_save(const char *filename, uint8_t *bitmap, int w, int h,
     f = fopen(fname, "w");
     if (!f) {
         perror(fname);
-        exit(1);
+        return;
     }
     fprintf(f, "P6\n"
             "%d %d\n"
@@ -73,7 +70,7 @@ static void png_save(const char *filename, uint8_t *bitmap, int w, int h,
     f = fopen(fname2, "w");
     if (!f) {
         perror(fname2);
-        exit(1);
+        return;
     }
     fprintf(f, "P5\n"
             "%d %d\n"
@@ -107,7 +104,7 @@ static void png_save2(const char *filename, uint32_t *bitmap, int w, int h)
     f = fopen(fname, "w");
     if (!f) {
         perror(fname);
-        exit(1);
+        return;
     }
     fprintf(f, "P6\n"
             "%d %d\n"
@@ -129,7 +126,7 @@ static void png_save2(const char *filename, uint32_t *bitmap, int w, int h)
     f = fopen(fname2, "w");
     if (!f) {
         perror(fname2);
-        exit(1);
+        return;
     }
     fprintf(f, "P5\n"
             "%d %d\n"
@@ -151,7 +148,7 @@ static void png_save2(const char *filename, uint32_t *bitmap, int w, int h)
 }
 #endif
 
-#define RGBA(r,g,b,a) (((a) << 24) | ((r) << 16) | ((g) << 8) | (b))
+#define RGBA(r,g,b,a) (((unsigned)(a) << 24) | ((r) << 16) | ((g) << 8) | (b))
 
 typedef struct DVBSubCLUT {
     int id;
@@ -216,6 +213,15 @@ typedef struct DVBSubRegion {
     struct DVBSubRegion *next;
 } DVBSubRegion;
 
+typedef struct DVBSubDisplayDefinition {
+    int version;
+
+    int x;
+    int y;
+    int width;
+    int height;
+} DVBSubDisplayDefinition;
+
 typedef struct DVBSubContext {
     int composition_id;
     int ancillary_id;
@@ -227,6 +233,7 @@ typedef struct DVBSubContext {
 
     int display_list_size;
     DVBSubRegionDisplay *display_list;
+    DVBSubDisplayDefinition *display_definition;
 } DVBSubContext;
 
 
@@ -320,9 +327,7 @@ static void delete_state(DVBSubContext *ctx)
         ctx->region_list = region->next;
 
         delete_region_display_list(ctx, region);
-        if (region->pbuf)
-            av_free(region->pbuf);
-
+        av_free(region->pbuf);
         av_free(region);
     }
 
@@ -334,6 +339,8 @@ static void delete_state(DVBSubContext *ctx)
         av_free(clut);
     }
 
+    av_freep(&ctx->display_definition);
+
     /* Should already be null */
     if (ctx->object_list)
         av_log(0, AV_LOG_ERROR, "Memory deallocation error!\n");
@@ -342,12 +349,16 @@ static void delete_state(DVBSubContext *ctx)
 static av_cold int dvbsub_init_decoder(AVCodecContext *avctx)
 {
     int i, r, g, b, a = 0;
-    DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;
-
-    memset(avctx->priv_data, 0, sizeof(DVBSubContext));
+    DVBSubContext *ctx = avctx->priv_data;
 
-    ctx->composition_id = avctx->sub_id & 0xffff;
-    ctx->ancillary_id = avctx->sub_id >> 16;
+    if (!avctx->extradata || avctx->extradata_size != 4) {
+        av_log(avctx, AV_LOG_WARNING, "Invalid extradata, subtitle streams may be combined!\n");
+        ctx->composition_id = -1;
+        ctx->ancillary_id   = -1;
+    } else {
+        ctx->composition_id = AV_RB16(avctx->extradata);
+        ctx->ancillary_id   = AV_RB16(avctx->extradata + 2);
+    }
 
     default_clut.id = -1;
     default_clut.next = NULL;
@@ -414,7 +425,7 @@ static av_cold int dvbsub_init_decoder(AVCodecContext *avctx)
 
 static av_cold int dvbsub_close_decoder(AVCodecContext *avctx)
 {
-    DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;
+    DVBSubContext *ctx = avctx->priv_data;
     DVBSubRegionDisplay *display;
 
     delete_state(ctx);
@@ -439,9 +450,9 @@ static int dvbsub_read_2bit_string(uint8_t *destbuf, int dbuf_len,
     int run_length;
     int pixels_read = 0;
 
-    init_get_bits(&gb, *srcbuf, buf_size << 8);
+    init_get_bits(&gb, *srcbuf, buf_size << 3);
 
-    while (get_bits_count(&gb) < (buf_size << 8) && pixels_read < dbuf_len) {
+    while (get_bits_count(&gb) < buf_size << 3 && pixels_read < dbuf_len) {
         bits = get_bits(&gb, 2);
 
         if (bits) {
@@ -544,9 +555,9 @@ static int dvbsub_read_4bit_string(uint8_t *destbuf, int dbuf_len,
     int run_length;
     int pixels_read = 0;
 
-    init_get_bits(&gb, *srcbuf, buf_size << 8);
+    init_get_bits(&gb, *srcbuf, buf_size << 3);
 
-    while (get_bits_count(&gb) < (buf_size << 8) && pixels_read < dbuf_len) {
+    while (get_bits_count(&gb) < buf_size << 3 && pixels_read < dbuf_len) {
         bits = get_bits(&gb, 4);
 
         if (bits) {
@@ -682,26 +693,19 @@ static int dvbsub_read_8bit_string(uint8_t *destbuf, int dbuf_len,
                 if (run_length == 0) {
                     return pixels_read;
                 }
-
-                if (map_table)
-                    bits = map_table[0];
-                else
-                    bits = 0;
-                while (run_length-- > 0 && pixels_read < dbuf_len) {
-                    *destbuf++ = bits;
-                    pixels_read++;
-                }
             } else {
                 bits = *(*srcbuf)++;
 
                 if (non_mod == 1 && bits == 1)
                     pixels_read += run_length;
-                if (map_table)
-                    bits = map_table[bits];
-                else while (run_length-- > 0 && pixels_read < dbuf_len) {
-                    *destbuf++ = bits;
-                    pixels_read++;
-                }
+            }
+            if (map_table)
+                bits = map_table[0];
+            else
+                bits = 0;
+            while (run_length-- > 0 && pixels_read < dbuf_len) {
+                *destbuf++ = bits;
+                pixels_read++;
             }
         }
     }
@@ -717,7 +721,7 @@ static int dvbsub_read_8bit_string(uint8_t *destbuf, int dbuf_len,
 static void dvbsub_parse_pixel_data_block(AVCodecContext *avctx, DVBSubObjectDisplay *display,
                                           const uint8_t *buf, int buf_size, int top_bottom, int non_mod)
 {
-    DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;
+    DVBSubContext *ctx = avctx->priv_data;
 
     DVBSubRegion *region = get_region(ctx, display->region_id);
     const uint8_t *buf_end = buf + buf_size;
@@ -731,25 +735,20 @@ static void dvbsub_parse_pixel_data_block(AVCodecContext *avctx, DVBSubObjectDis
                          0x88, 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff};
     uint8_t *map_table;
 
-#ifdef DEBUG
-    av_log(avctx, AV_LOG_INFO, "DVB pixel block size %d, %s field:\n", buf_size,
-                top_bottom ? "bottom" : "top");
-#endif
+    av_dlog(avctx, "DVB pixel block size %d, %s field:\n", buf_size,
+            top_bottom ? "bottom" : "top");
 
-#ifdef DEBUG_PACKET_CONTENTS
     for (i = 0; i < buf_size; i++) {
         if (i % 16 == 0)
-            av_log(avctx, AV_LOG_INFO, "0x%08p: ", buf+i);
+            av_dlog(avctx, "0x%8p: ", buf+i);
 
-        av_log(avctx, AV_LOG_INFO, "%02x ", buf[i]);
+        av_dlog(avctx, "%02x ", buf[i]);
         if (i % 16 == 15)
-            av_log(avctx, AV_LOG_INFO, "\n");
+            av_dlog(avctx, "\n");
     }
 
     if (i % 16)
-        av_log(avctx, AV_LOG_INFO, "\n");
-
-#endif
+        av_dlog(avctx, "\n");
 
     if (region == 0)
         return;
@@ -778,7 +777,7 @@ static void dvbsub_parse_pixel_data_block(AVCodecContext *avctx, DVBSubObjectDis
                 map_table = NULL;
 
             x_pos += dvbsub_read_2bit_string(pbuf + (y_pos * region->width) + x_pos,
-                                                region->width - x_pos, &buf, buf_size,
+                                                region->width - x_pos, &buf, buf_end - buf,
                                                 non_mod, map_table);
             break;
         case 0x11:
@@ -793,7 +792,7 @@ static void dvbsub_parse_pixel_data_block(AVCodecContext *avctx, DVBSubObjectDis
                 map_table = NULL;
 
             x_pos += dvbsub_read_4bit_string(pbuf + (y_pos * region->width) + x_pos,
-                                                region->width - x_pos, &buf, buf_size,
+                                                region->width - x_pos, &buf, buf_end - buf,
                                                 non_mod, map_table);
             break;
         case 0x12:
@@ -803,7 +802,7 @@ static void dvbsub_parse_pixel_data_block(AVCodecContext *avctx, DVBSubObjectDis
             }
 
             x_pos += dvbsub_read_8bit_string(pbuf + (y_pos * region->width) + x_pos,
-                                                region->width - x_pos, &buf, buf_size,
+                                                region->width - x_pos, &buf, buf_end - buf,
                                                 non_mod, NULL);
             break;
 
@@ -833,10 +832,10 @@ static void dvbsub_parse_pixel_data_block(AVCodecContext *avctx, DVBSubObjectDis
 
 }
 
-static void dvbsub_parse_object_segment(AVCodecContext *avctx,
-                                        const uint8_t *buf, int buf_size)
+static int dvbsub_parse_object_segment(AVCodecContext *avctx,
+                                       const uint8_t *buf, int buf_size)
 {
-    DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;
+    DVBSubContext *ctx = avctx->priv_data;
 
     const uint8_t *buf_end = buf + buf_size;
     const uint8_t *block;
@@ -853,7 +852,7 @@ static void dvbsub_parse_object_segment(AVCodecContext *avctx,
     object = get_object(ctx, object_id);
 
     if (!object)
-        return;
+        return AVERROR_INVALIDDATA;
 
     coding_method = ((*buf) >> 2) & 3;
     non_modifying_color = ((*buf++) >> 1) & 1;
@@ -866,7 +865,7 @@ static void dvbsub_parse_object_segment(AVCodecContext *avctx,
 
         if (buf + top_field_len + bottom_field_len > buf_end) {
             av_log(avctx, AV_LOG_ERROR, "Field data size too large\n");
-            return;
+            return AVERROR_INVALIDDATA;
         }
 
         for (display = object->display_list; display; display = display->object_list_next) {
@@ -890,35 +889,31 @@ static void dvbsub_parse_object_segment(AVCodecContext *avctx,
         av_log(avctx, AV_LOG_ERROR, "Unknown object coding %d\n", coding_method);
     }
 
+    return 0;
 }
 
-static void dvbsub_parse_clut_segment(AVCodecContext *avctx,
-                                        const uint8_t *buf, int buf_size)
+static int dvbsub_parse_clut_segment(AVCodecContext *avctx,
+                                     const uint8_t *buf, int buf_size)
 {
-    DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;
+    DVBSubContext *ctx = avctx->priv_data;
 
     const uint8_t *buf_end = buf + buf_size;
-    int clut_id;
+    int i, clut_id;
     DVBSubCLUT *clut;
     int entry_id, depth , full_range;
     int y, cr, cb, alpha;
     int r, g, b, r_add, g_add, b_add;
 
-#ifdef DEBUG_PACKET_CONTENTS
-    int i;
-
-    av_log(avctx, AV_LOG_INFO, "DVB clut packet:\n");
+    av_dlog(avctx, "DVB clut packet:\n");
 
     for (i=0; i < buf_size; i++) {
-        av_log(avctx, AV_LOG_INFO, "%02x ", buf[i]);
+        av_dlog(avctx, "%02x ", buf[i]);
         if (i % 16 == 15)
-            av_log(avctx, AV_LOG_INFO, "\n");
+            av_dlog(avctx, "\n");
     }
 
     if (i % 16)
-        av_log(avctx, AV_LOG_INFO, "\n");
-
-#endif
+        av_dlog(avctx, "\n");
 
     clut_id = *buf++;
     buf += 1;
@@ -927,6 +922,8 @@ static void dvbsub_parse_clut_segment(AVCodecContext *avctx,
 
     if (!clut) {
         clut = av_malloc(sizeof(DVBSubCLUT));
+        if (!clut)
+            return AVERROR(ENOMEM);
 
         memcpy(clut, &default_clut, sizeof(DVBSubCLUT));
 
@@ -943,7 +940,7 @@ static void dvbsub_parse_clut_segment(AVCodecContext *avctx,
 
         if (depth == 0) {
             av_log(avctx, AV_LOG_ERROR, "Invalid clut depth 0x%x!\n", *buf);
-            return;
+            return AVERROR_INVALIDDATA;
         }
 
         full_range = (*buf++) & 1;
@@ -968,9 +965,7 @@ static void dvbsub_parse_clut_segment(AVCodecContext *avctx,
         YUV_TO_RGB1_CCIR(cb, cr);
         YUV_TO_RGB2_CCIR(r, g, b, y);
 
-#ifdef DEBUG
-        av_log(avctx, AV_LOG_INFO, "clut %d := (%d,%d,%d,%d)\n", entry_id, r, g, b, alpha);
-#endif
+        av_dlog(avctx, "clut %d := (%d,%d,%d,%d)\n", entry_id, r, g, b, alpha);
 
         if (depth & 0x80)
             clut->clut4[entry_id] = RGBA(r,g,b,255 - alpha);
@@ -979,13 +974,15 @@ static void dvbsub_parse_clut_segment(AVCodecContext *avctx,
         if (depth & 0x20)
             clut->clut256[entry_id] = RGBA(r,g,b,255 - alpha);
     }
+
+    return 0;
 }
 
 
-static void dvbsub_parse_region_segment(AVCodecContext *avctx,
-                                        const uint8_t *buf, int buf_size)
+static int dvbsub_parse_region_segment(AVCodecContext *avctx,
+                                       const uint8_t *buf, int buf_size)
 {
-    DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;
+    DVBSubContext *ctx = avctx->priv_data;
 
     const uint8_t *buf_end = buf + buf_size;
     int region_id, object_id;
@@ -995,7 +992,7 @@ static void dvbsub_parse_region_segment(AVCodecContext *avctx,
     int fill;
 
     if (buf_size < 10)
-        return;
+        return AVERROR_INVALIDDATA;
 
     region_id = *buf++;
 
@@ -1003,6 +1000,8 @@ static void dvbsub_parse_region_segment(AVCodecContext *avctx,
 
     if (!region) {
         region = av_mallocz(sizeof(DVBSubRegion));
+        if (!region)
+            return AVERROR(ENOMEM);
 
         region->id = region_id;
 
@@ -1018,12 +1017,13 @@ static void dvbsub_parse_region_segment(AVCodecContext *avctx,
     buf += 2;
 
     if (region->width * region->height != region->buf_size) {
-        if (region->pbuf)
-            av_free(region->pbuf);
+        av_free(region->pbuf);
 
         region->buf_size = region->width * region->height;
 
         region->pbuf = av_malloc(region->buf_size);
+        if (!region->pbuf)
+            return AVERROR(ENOMEM);
 
         fill = 1;
     }
@@ -1046,15 +1046,11 @@ static void dvbsub_parse_region_segment(AVCodecContext *avctx,
             region->bgcolor = (((*buf++) >> 2) & 3);
     }
 
-#ifdef DEBUG
-    av_log(avctx, AV_LOG_INFO, "Region %d, (%dx%d)\n", region_id, region->width, region->height);
-#endif
+    av_dlog(avctx, "Region %d, (%dx%d)\n", region_id, region->width, region->height);
 
     if (fill) {
         memset(region->pbuf, region->bgcolor, region->buf_size);
-#ifdef DEBUG
-        av_log(avctx, AV_LOG_INFO, "Fill region (%d)\n", region->bgcolor);
-#endif
+        av_dlog(avctx, "Fill region (%d)\n", region->bgcolor);
     }
 
     delete_region_display_list(ctx, region);
@@ -1067,6 +1063,8 @@ static void dvbsub_parse_region_segment(AVCodecContext *avctx,
 
         if (!object) {
             object = av_mallocz(sizeof(DVBSubObject));
+            if (!object)
+                return AVERROR(ENOMEM);
 
             object->id = object_id;
             object->next = ctx->object_list;
@@ -1076,6 +1074,8 @@ static void dvbsub_parse_region_segment(AVCodecContext *avctx,
         object->type = (*buf) >> 6;
 
         display = av_mallocz(sizeof(DVBSubObjectDisplay));
+        if (!display)
+            return AVERROR(ENOMEM);
 
         display->object_id = object_id;
         display->region_id = region_id;
@@ -1096,12 +1096,14 @@ static void dvbsub_parse_region_segment(AVCodecContext *avctx,
         display->object_list_next = object->display_list;
         object->display_list = display;
     }
+
+    return 0;
 }
 
-static void dvbsub_parse_page_segment(AVCodecContext *avctx,
-                                        const uint8_t *buf, int buf_size)
+static int dvbsub_parse_page_segment(AVCodecContext *avctx,
+                                     const uint8_t *buf, int buf_size)
 {
-    DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;
+    DVBSubContext *ctx = avctx->priv_data;
     DVBSubRegionDisplay *display;
     DVBSubRegionDisplay *tmp_display_list, **tmp_ptr;
 
@@ -1110,14 +1112,12 @@ static void dvbsub_parse_page_segment(AVCodecContext *avctx,
     int page_state;
 
     if (buf_size < 1)
-        return;
+        return AVERROR_INVALIDDATA;
 
     ctx->time_out = *buf++;
     page_state = ((*buf++) >> 2) & 3;
 
-#ifdef DEBUG
-    av_log(avctx, AV_LOG_INFO, "Page time out %ds, state %d\n", ctx->time_out, page_state);
-#endif
+    av_dlog(avctx, "Page time out %ds, state %d\n", ctx->time_out, page_state);
 
     if (page_state == 2) {
         delete_state(ctx);
@@ -1139,8 +1139,11 @@ static void dvbsub_parse_page_segment(AVCodecContext *avctx,
             display = display->next;
         }
 
-        if (!display)
+        if (!display) {
             display = av_mallocz(sizeof(DVBSubRegionDisplay));
+            if (!display)
+                return AVERROR(ENOMEM);
+        }
 
         display->region_id = region_id;
 
@@ -1155,9 +1158,7 @@ static void dvbsub_parse_page_segment(AVCodecContext *avctx,
         ctx->display_list = display;
         ctx->display_list_size++;
 
-#ifdef DEBUG
-        av_log(avctx, AV_LOG_INFO, "Region %d, (%d,%d)\n", region_id, display->x_pos, display->y_pos);
-#endif
+        av_dlog(avctx, "Region %d, (%d,%d)\n", region_id, display->x_pos, display->y_pos);
     }
 
     while (tmp_display_list) {
@@ -1168,10 +1169,11 @@ static void dvbsub_parse_page_segment(AVCodecContext *avctx,
         av_free(display);
     }
 
+    return 0;
 }
 
 
-#ifdef DEBUG_SAVE_IMAGES
+#ifdef DEBUG
 static void save_display_set(DVBSubContext *ctx)
 {
     DVBSubRegion *region;
@@ -1221,6 +1223,8 @@ static void save_display_set(DVBSubContext *ctx)
     if (x_pos >= 0) {
 
         pbuf = av_malloc(width * height * 4);
+        if (!pbuf)
+            return AVERROR(ENOMEM);
 
         for (display = ctx->display_list; display; display = display->next) {
             region = get_region(ctx, display->region_id);
@@ -1266,10 +1270,53 @@ static void save_display_set(DVBSubContext *ctx)
 }
 #endif
 
+static int dvbsub_parse_display_definition_segment(AVCodecContext *avctx,
+                                                   const uint8_t *buf,
+                                                   int buf_size)
+{
+    DVBSubContext *ctx = avctx->priv_data;
+    DVBSubDisplayDefinition *display_def = ctx->display_definition;
+    int dds_version, info_byte;
+
+    if (buf_size < 5)
+        return AVERROR_INVALIDDATA;
+
+    info_byte   = bytestream_get_byte(&buf);
+    dds_version = info_byte >> 4;
+    if (display_def && display_def->version == dds_version)
+        return 0; // already have this display definition version
+
+    if (!display_def) {
+        display_def             = av_mallocz(sizeof(*display_def));
+        if (!display_def)
+            return AVERROR(ENOMEM);
+        ctx->display_definition = display_def;
+    }
+
+    display_def->version = dds_version;
+    display_def->x       = 0;
+    display_def->y       = 0;
+    display_def->width   = bytestream_get_be16(&buf) + 1;
+    display_def->height  = bytestream_get_be16(&buf) + 1;
+
+    if (buf_size < 13)
+        return AVERROR_INVALIDDATA;
+
+    if (info_byte & 1<<3) { // display_window_flag
+        display_def->x = bytestream_get_be16(&buf);
+        display_def->y = bytestream_get_be16(&buf);
+        display_def->width  = bytestream_get_be16(&buf) - display_def->x + 1;
+        display_def->height = bytestream_get_be16(&buf) - display_def->y + 1;
+    }
+
+    return 0;
+}
+
 static int dvbsub_display_end_segment(AVCodecContext *avctx, const uint8_t *buf,
-                                        int buf_size, AVSubtitle *sub)
+                                      int buf_size, AVSubtitle *sub)
 {
-    DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;
+    DVBSubContext *ctx = avctx->priv_data;
+    DVBSubDisplayDefinition *display_def = ctx->display_definition;
 
     DVBSubRegion *region;
     DVBSubRegionDisplay *display;
@@ -1277,19 +1324,26 @@ static int dvbsub_display_end_segment(AVCodecContext *avctx, const uint8_t *buf,
     DVBSubCLUT *clut;
     uint32_t *clut_table;
     int i;
+    int offset_x=0, offset_y=0;
 
     sub->rects = NULL;
     sub->start_display_time = 0;
     sub->end_display_time = ctx->time_out * 1000;
     sub->format = 0;
 
+    if (display_def) {
+        offset_x = display_def->x;
+        offset_y = display_def->y;
+    }
+
     sub->num_rects = ctx->display_list_size;
+    if (sub->num_rects <= 0)
+        return AVERROR_INVALIDDATA;
 
-    if (sub->num_rects > 0){
-        sub->rects = av_mallocz(sizeof(*sub->rects) * sub->num_rects);
-        for(i=0; i<sub->num_rects; i++)
-            sub->rects[i] = av_mallocz(sizeof(*sub->rects[i]));
-    }
+    sub->rects = av_mallocz_array(sub->num_rects * sub->num_rects,
+                                  sizeof(*sub->rects));
+    if (!sub->rects)
+        return AVERROR(ENOMEM);
 
     i = 0;
 
@@ -1300,11 +1354,12 @@ static int dvbsub_display_end_segment(AVCodecContext *avctx, const uint8_t *buf,
         if (!region)
             continue;
 
-        rect->x = display->x_pos;
-        rect->y = display->y_pos;
+        rect->x = display->x_pos + offset_x;
+        rect->y = display->y_pos + offset_y;
         rect->w = region->width;
         rect->h = region->height;
         rect->nb_colors = 16;
+        rect->type      = SUBTITLE_BITMAP;
         rect->pict.linesize[0] = region->width;
 
         clut = get_clut(ctx, region->clut);
@@ -1325,10 +1380,19 @@ static int dvbsub_display_end_segment(AVCodecContext *avctx, const uint8_t *buf,
             break;
         }
 
-        rect->pict.data[1] = av_malloc((1 << region->depth) * sizeof(uint32_t));
+        rect->pict.data[1] = av_mallocz(AVPALETTE_SIZE);
+        if (!rect->pict.data[1]) {
+            av_free(sub->rects);
+            return AVERROR(ENOMEM);
+        }
         memcpy(rect->pict.data[1], clut_table, (1 << region->depth) * sizeof(uint32_t));
 
         rect->pict.data[0] = av_malloc(region->buf_size);
+        if (!rect->pict.data[0]) {
+            av_free(rect->pict.data[1]);
+            av_free(sub->rects);
+            return AVERROR(ENOMEM);
+        }
         memcpy(rect->pict.data[0], region->pbuf, region->buf_size);
 
         i++;
@@ -1336,7 +1400,7 @@ static int dvbsub_display_end_segment(AVCodecContext *avctx, const uint8_t *buf,
 
     sub->num_rects = i;
 
-#ifdef DEBUG_SAVE_IMAGES
+#ifdef DEBUG
     save_display_set(ctx);
 #endif
 
@@ -1345,38 +1409,38 @@ static int dvbsub_display_end_segment(AVCodecContext *avctx, const uint8_t *buf,
 
 static int dvbsub_decode(AVCodecContext *avctx,
                          void *data, int *data_size,
-                         const uint8_t *buf, int buf_size)
+                         AVPacket *avpkt)
 {
-    DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;
-    AVSubtitle *sub = (AVSubtitle*) data;
+    const uint8_t *buf = avpkt->data;
+    int buf_size = avpkt->size;
+    DVBSubContext *ctx = avctx->priv_data;
+    AVSubtitle *sub = data;
     const uint8_t *p, *p_end;
     int segment_type;
     int page_id;
     int segment_length;
-
-#ifdef DEBUG_PACKET_CONTENTS
     int i;
 
-    av_log(avctx, AV_LOG_INFO, "DVB sub packet:\n");
+    av_dlog(avctx, "DVB sub packet:\n");
 
     for (i=0; i < buf_size; i++) {
-        av_log(avctx, AV_LOG_INFO, "%02x ", buf[i]);
+        av_dlog(avctx, "%02x ", buf[i]);
         if (i % 16 == 15)
-            av_log(avctx, AV_LOG_INFO, "\n");
+            av_dlog(avctx, "\n");
     }
 
     if (i % 16)
-        av_log(avctx, AV_LOG_INFO, "\n");
+        av_dlog(avctx, "\n");
 
-#endif
-
-    if (buf_size <= 2)
-        return -1;
+    if (buf_size <= 6 || *buf != 0x0f) {
+        av_dlog(avctx, "incomplete or broken packet");
+        return AVERROR_INVALIDDATA;
+    }
 
     p = buf;
     p_end = buf + buf_size;
 
-    while (p < p_end && *p == 0x0f) {
+    while (p_end - p >= 6 && *p == 0x0f) {
         p += 1;
         segment_type = *p++;
         page_id = AV_RB16(p);
@@ -1384,54 +1448,58 @@ static int dvbsub_decode(AVCodecContext *avctx,
         segment_length = AV_RB16(p);
         p += 2;
 
-        if (page_id == ctx->composition_id || page_id == ctx->ancillary_id) {
+        if (p_end - p < segment_length) {
+            av_dlog(avctx, "incomplete or broken packet");
+            return -1;
+        }
+
+        if (page_id == ctx->composition_id || page_id == ctx->ancillary_id ||
+            ctx->composition_id == -1 || ctx->ancillary_id == -1) {
+            int ret = 0;
             switch (segment_type) {
             case DVBSUB_PAGE_SEGMENT:
-                dvbsub_parse_page_segment(avctx, p, segment_length);
+                ret = dvbsub_parse_page_segment(avctx, p, segment_length);
                 break;
             case DVBSUB_REGION_SEGMENT:
-                dvbsub_parse_region_segment(avctx, p, segment_length);
+                ret = dvbsub_parse_region_segment(avctx, p, segment_length);
                 break;
             case DVBSUB_CLUT_SEGMENT:
-                dvbsub_parse_clut_segment(avctx, p, segment_length);
+                ret = dvbsub_parse_clut_segment(avctx, p, segment_length);
                 break;
             case DVBSUB_OBJECT_SEGMENT:
-                dvbsub_parse_object_segment(avctx, p, segment_length);
+                ret = dvbsub_parse_object_segment(avctx, p, segment_length);
+                break;
+            case DVBSUB_DISPLAYDEFINITION_SEGMENT:
+                ret = dvbsub_parse_display_definition_segment(avctx, p,
+                                                              segment_length);
                 break;
             case DVBSUB_DISPLAY_SEGMENT:
-                *data_size = dvbsub_display_end_segment(avctx, p, segment_length, sub);
+                ret = dvbsub_display_end_segment(avctx, p, segment_length, sub);
+                *data_size = ret;
                 break;
             default:
-#ifdef DEBUG
-                av_log(avctx, AV_LOG_INFO, "Subtitling segment type 0x%x, page id %d, length %d\n",
+                av_dlog(avctx, "Subtitling segment type 0x%x, page id %d, length %d\n",
                         segment_type, page_id, segment_length);
-#endif
                 break;
             }
+            if (ret < 0)
+                return ret;
         }
 
         p += segment_length;
     }
 
-    if (p != p_end) {
-#ifdef DEBUG
-        av_log(avctx, AV_LOG_INFO, "Junk at end of packet\n");
-#endif
-        return -1;
-    }
-
-    return buf_size;
+    return p - buf;
 }
 
 
-AVCodec dvbsub_decoder = {
-    "dvbsub",
-    CODEC_TYPE_SUBTITLE,
-    CODEC_ID_DVB_SUBTITLE,
-    sizeof(DVBSubContext),
-    dvbsub_init_decoder,
-    NULL,
-    dvbsub_close_decoder,
-    dvbsub_decode,
-    .long_name = NULL_IF_CONFIG_SMALL("DVB subtitles"),
+AVCodec ff_dvbsub_decoder = {
+    .name           = "dvbsub",
+    .long_name      = NULL_IF_CONFIG_SMALL("DVB subtitles"),
+    .type           = AVMEDIA_TYPE_SUBTITLE,
+    .id             = AV_CODEC_ID_DVB_SUBTITLE,
+    .priv_data_size = sizeof(DVBSubContext),
+    .init           = dvbsub_init_decoder,
+    .close          = dvbsub_close_decoder,
+    .decode         = dvbsub_decode,
 };