These changes allow testing Bluray IGS HDMV menu with avplay:
- add support for display overlay pictures,
- add support for openning a second input file as subpath,
- add some basic navigation commands to simulate and view
  result of pages and buttons (p/u/d/l/r/enter keys).

One thing don't work well now: backup/restore of YUV buffer
to allow display of menu even if video stream reach the end
(like mpeg2video stream with only one frame used in static
menu)

version 4:
- Remove RGBA->YUVA palette convertion for overlay. Palette
  already in YUVA CCIR now.

Signed-off-by: David Girault <david at dhgirault.fr>
---
 avplay.c |  593 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 542 insertions(+), 51 deletions(-)

diff --git a/avplay.c b/avplay.c
index c01e446..5eae23e 100644
--- a/avplay.c
+++ b/avplay.c
@@ -118,6 +118,11 @@ typedef struct SubPicture {
     AVSubtitle sub;
 } SubPicture;
 
+typedef struct OverlayPicture {
+    double pts; /* presentation time stamp for this picture */
+    AVOverlay  overlay;
+} OverlayPicture;
+
 enum {
     AV_SYNC_AUDIO_MASTER, /* default choice */
     AV_SYNC_VIDEO_MASTER,
@@ -188,6 +193,23 @@ typedef struct VideoState {
     SDL_mutex *subpq_mutex;
     SDL_cond *subpq_cond;
 
+    char overlay_subpath[1024];
+    int overlay_use_subpath;
+    AVFormatContext *overlay_ic;
+
+    SDL_Thread *overlay_tid;
+    int overlay_stream;
+    int overlay_stream_changed;
+    AVStream *overlay_st;
+    SDL_Overlay *overlay_bmp;                   ///< Used to display an overlay picture when no new video picture is available
+    double overlay_last_pts;
+    PacketQueue overlayq;
+    OverlayPicture ovepq[SUBPICTURE_QUEUE_SIZE];
+    int ovepq_size, ovepq_rindex, ovepq_windex;
+    SDL_mutex *ovepq_mutex;
+    SDL_cond *ovepq_cond;
+
+    double aspect_ratio;                        ///< calculated when video picture is displayed
     double frame_timer;
     double frame_last_pts;
     double frame_last_delay;
@@ -208,6 +230,7 @@ typedef struct VideoState {
 
     //    QETimer *video_timer;
     char filename[1024];
+   
     int width, height, xleft, ytop;
 
     PtsCorrectionContext pts_ctx;
@@ -225,10 +248,12 @@ typedef struct VideoState {
 } VideoState;
 
 static void show_help(void);
+static void stream_handle_event(VideoState *is, SDL_Event *event);
 
 /* options specified by the user */
 static AVInputFormat *file_iformat;
 static const char *input_filename;
+static const char *subpath_filename;
 static const char *window_title;
 static int fs_screen_width;
 static int fs_screen_height;
@@ -240,6 +265,7 @@ static int wanted_stream[AVMEDIA_TYPE_NB] = {
     [AVMEDIA_TYPE_AUDIO]    = -1,
     [AVMEDIA_TYPE_VIDEO]    = -1,
     [AVMEDIA_TYPE_SUBTITLE] = -1,
+    [AVMEDIA_TYPE_OVERLAY]  = -1,
 };
 static int seek_by_bytes = -1;
 static int display_disable;
@@ -442,7 +468,9 @@ static inline void fill_rectangle(SDL_Surface *screen,
 
 #define BPP 1
 
-static void blend_subrect(AVPicture *dst, const AVSubtitleRect *rect, int imgw, int imgh)
+static void blend_rect(AVPicture *dst, int imgw, int imgh, 
+                       int rw, int rh, int rx, int ry, 
+                       Uint8 *pixels, Uint8 *palette, int linesize)
 {
     int wrap, wrap3, width2, skip2;
     int y, u, v, a, u1, v1, a1, w, h;
@@ -451,10 +479,10 @@ static void blend_subrect(AVPicture *dst, const AVSubtitleRect *rect, int imgw,
     const uint32_t *pal;
     int dstx, dsty, dstw, dsth;
 
-    dstw = av_clip(rect->w, 0, imgw);
-    dsth = av_clip(rect->h, 0, imgh);
-    dstx = av_clip(rect->x, 0, imgw - dstw);
-    dsty = av_clip(rect->y, 0, imgh - dsth);
+    dstw = av_clip(rw, 0, imgw);
+    dsth = av_clip(rh, 0, imgh);
+    dstx = av_clip(rx, 0, imgw - dstw);
+    dsty = av_clip(ry, 0, imgh - dsth);
     lum = dst->data[0] + dsty * dst->linesize[0];
     cb  = dst->data[1] + (dsty >> 1) * dst->linesize[1];
     cr  = dst->data[2] + (dsty >> 1) * dst->linesize[2];
@@ -462,9 +490,9 @@ static void blend_subrect(AVPicture *dst, const AVSubtitleRect *rect, int imgw,
     width2 = ((dstw + 1) >> 1) + (dstx & ~dstw & 1);
     skip2 = dstx >> 1;
     wrap = dst->linesize[0];
-    wrap3 = rect->pict.linesize[0];
-    p = rect->pict.data[0];
-    pal = (const uint32_t *)rect->pict.data[1];  /* Now in YCrCb! */
+    wrap3 = linesize;
+    p = pixels;
+    pal = (const uint32_t *)palette;  /* Now in YCrCb! */
 
     if (dsty & 1) {
         lum += dstx;
@@ -642,17 +670,181 @@ static void blend_subrect(AVPicture *dst, const AVSubtitleRect *rect, int imgw,
     }
 }
 
+static inline void blend_subrect(AVPicture *dst, const AVSubtitleRect *rect, int imgw, int imgh)
+{
+    blend_rect(dst, imgw, imgh, 
+               rect->w, rect->h, rect->x, rect->y,
+               rect->pict.data[0],
+               rect->pict.data[1],
+               rect->pict.linesize[0]);
+}
+
+static inline void blend_overlayrect(AVPicture *dst, const AVOverlayRect *rect, int imgw, int imgh)
+{
+    blend_rect(dst, imgw, imgh, 
+               rect->w, rect->h, rect->x, rect->y,
+               rect->pict.data[0],
+               rect->pict.data[1],
+               rect->pict.linesize[0]);
+}
+
 static void free_subpicture(SubPicture *sp)
 {
     avsubtitle_free(&sp->sub);
 }
 
+static void free_overlaypicture(OverlayPicture *op)
+{
+    avoverlay_free(&op->overlay);
+}
+
+
+static inline void overlay_img_backup(SDL_Overlay *bmp, Uint8 **bakpixels)
+{
+    int i;
+    for (i=0;i<bmp->planes;i++) {
+        bakpixels[i] = av_malloc(bmp->pitches[i]);
+        memcpy(bakpixels[i], bmp->pixels[i], bmp->pitches[i]);
+    }
+}
+static inline void overlay_img_restore(SDL_Overlay *bmp, Uint8 **bakpixels)
+{
+    int i;
+    for (i=0;i<bmp->planes;i++) {
+        memcpy(bmp->pixels[i], bakpixels[i], bmp->pitches[i]);
+        av_freep(&bakpixels[i]);
+    }
+}
+
+static void overlay_image_display(VideoState *is, SDL_Overlay *bmp, SDL_Rect *rectp)
+{
+    // if rectp not NULL, we are called from video_image_display, after video picture was displayed.
+    // need to backup altered surfaces but don't require to restore previous saved surfaces.
+    // if rectp is NULL, we need to restore previous saved surfaces before drawing new overlay pic.
+    OverlayPicture *sp;
+    AVPicture pict;
+    SDL_Rect rect;
+    int i, deleted=0;
+    
+    if (rectp == NULL) {
+        int width, height, x, y;
+        // 
+        height = is->height;
+        width = ((int)rint(height * is->aspect_ratio)) & ~1;
+        if (width > is->width) {
+            width = is->width;
+            height = ((int)rint(width / is->aspect_ratio)) & ~1;
+        }
+        x = (is->width - width) / 2;
+        y = (is->height - height) / 2;
+        rect.x = is->xleft + x;
+        rect.y = is->ytop  + y;
+        rect.w = width;
+        rect.h = height;
+        rectp = &rect;
+    }
+
+    if (is->overlay_st) 
+    {
+        int num = 2; // number of overlay pictures to keep + 1
+        if (is->overlay_stream_changed) num--; // purge all on changed stream
+        
+        while (is->ovepq_size >= num) {
+            if (is->ovepq_size == num && !bmp && num == 1) {
+                /* previous displayed overlay pictures need to be removed from display */
+                av_dlog(NULL, "Remove older overlay picture by restoring original saved one: %dx%d@%d:%d\n", rectp->w,rectp->h,rectp->x,rectp->y);
+                SDL_DisplayYUVOverlay(is->overlay_bmp, rectp);
+            }
+            free_overlaypicture(&is->ovepq[is->ovepq_rindex]);
+            /* update queue size and signal for next picture */
+            if (++is->ovepq_rindex == SUBPICTURE_QUEUE_SIZE)
+                is->ovepq_rindex = 0;
+            is->ovepq_size--;
+            deleted++;
+        }
+
+        if (is->ovepq_size > 0)
+        {
+            sp = &is->ovepq[is->ovepq_rindex];
+
+            /*if (is->video_current_pts > (sp->pts + ((float) sp->overlay.end_display_time / 1000))) {
+                if (!bmp) {
+                    // restore last backup
+                    fprintf(stderr, "Overlay picture timed-out, !\n");
+                    SDL_DisplayYUVOverlay(is->overlay_bmp, rectp);
+                }
+                else {
+                    // do nothing, caller will display unmodified picture
+                }
+            }
+            else */
+            if (is->video_current_pts >= sp->pts + ((float) sp->overlay.start_display_time / 1000))
+            {
+                Uint8 *bakpixels[3]; // 3 pixels planes max
+                if (bmp) {
+                    // we have a new source, backup it then use it directly
+                    av_dlog(NULL, "Display current overlay picture on new video picture (%dx%d@%d:%d)\n", rectp->w,rectp->h,rectp->x,rectp->y);
+                    SDL_LockYUVOverlay(bmp);
+                    overlay_img_backup(bmp, bakpixels); // first, save unmodified picture
+
+                    // apply overlay pictures
+                    pict.data[0] = bmp->pixels[0];
+                    pict.data[1] = bmp->pixels[2];
+                    pict.data[2] = bmp->pixels[1];
+                    pict.linesize[0] = bmp->pitches[0];
+                    pict.linesize[1] = bmp->pitches[2];
+                    pict.linesize[2] = bmp->pitches[1];
+                    for (i = 0; i < sp->overlay.num_rects; i++)
+                        blend_overlayrect(&pict, sp->overlay.rects[i], bmp->w, bmp->h);
+                    SDL_UnlockYUVOverlay (bmp);
+
+                    // modified bmp displayed by caller, don't do it now
+
+                    // store backup in our overlay_bmp
+                    SDL_LockYUVOverlay(is->overlay_bmp);
+                    overlay_img_restore(is->overlay_bmp, bakpixels);
+                    SDL_UnlockYUVOverlay(is->overlay_bmp);
+                    is->overlay_last_pts = is->video_current_pts;
+                }
+                else if (deleted) {
+                    // we don't have a source, duplicate backup and use it
+                    av_dlog(NULL, "Display new overlay picture on old video picture (%dx%d@%d:%d)\n", rectp->w,rectp->h,rectp->x,rectp->y);
+                    SDL_LockYUVOverlay (is->overlay_bmp);
+                    overlay_img_backup(is->overlay_bmp, bakpixels);
+
+                    // apply overlay pictures
+                    pict.data[0] = is->overlay_bmp->pixels[0];
+                    pict.data[1] = is->overlay_bmp->pixels[2];
+                    pict.data[2] = is->overlay_bmp->pixels[1];
+                    pict.linesize[0] = is->overlay_bmp->pitches[0];
+                    pict.linesize[1] = is->overlay_bmp->pitches[2];
+                    pict.linesize[2] = is->overlay_bmp->pitches[1];
+                    for (i = 0; i < sp->overlay.num_rects; i++)
+                        blend_overlayrect(&pict, sp->overlay.rects[i], is->overlay_bmp->w, is->overlay_bmp->h);
+                    SDL_UnlockYUVOverlay (is->overlay_bmp);
+
+                    // display it right now
+                    SDL_DisplayYUVOverlay(is->overlay_bmp, rectp);
+
+                    // restore backup in our overlay_bmp
+                    SDL_LockYUVOverlay (is->overlay_bmp);
+                    overlay_img_restore(is->overlay_bmp, bakpixels);
+                    SDL_UnlockYUVOverlay (is->overlay_bmp);
+                }
+            }
+            else {
+                av_log(NULL, AV_LOG_DEBUG, "Don't display new overlay picture because of pts: %lf < %lf+(%d/1000)\n",
+                       is->video_current_pts, sp->pts,  sp->overlay.start_display_time);
+            }
+        }
+    }
+}
+
 static void video_image_display(VideoState *is)
 {
     VideoPicture *vp;
     SubPicture *sp;
     AVPicture pict;
-    float aspect_ratio;
     int width, height, x, y;
     SDL_Rect rect;
     int i;
@@ -661,22 +853,22 @@ static void video_image_display(VideoState *is)
     if (vp->bmp) {
 #if CONFIG_AVFILTER
          if (vp->picref->video->pixel_aspect.num == 0)
-             aspect_ratio = 0;
+             is->aspect_ratio = 0;
          else
-             aspect_ratio = av_q2d(vp->picref->video->pixel_aspect);
+             is->aspect_ratio = av_q2d(vp->picref->video->pixel_aspect);
 #else
 
         /* XXX: use variable in the frame */
         if (is->video_st->sample_aspect_ratio.num)
-            aspect_ratio = av_q2d(is->video_st->sample_aspect_ratio);
+            is->aspect_ratio = av_q2d(is->video_st->sample_aspect_ratio);
         else if (is->video_st->codec->sample_aspect_ratio.num)
-            aspect_ratio = av_q2d(is->video_st->codec->sample_aspect_ratio);
+            is->aspect_ratio = av_q2d(is->video_st->codec->sample_aspect_ratio);
         else
-            aspect_ratio = 0;
+            is->aspect_ratio = 0;
 #endif
-        if (aspect_ratio <= 0.0)
-            aspect_ratio = 1.0;
-        aspect_ratio *= (float)vp->width / (float)vp->height;
+        if (is->aspect_ratio <= 0.0)
+            is->aspect_ratio = 1.0;
+        is->aspect_ratio *= (float)vp->width / (float)vp->height;
 
         if (is->subtitle_st)
         {
@@ -705,13 +897,12 @@ static void video_image_display(VideoState *is)
             }
         }
 
-
         /* XXX: we suppose the screen has a 1.0 pixel ratio */
         height = is->height;
-        width = ((int)rint(height * aspect_ratio)) & ~1;
+        width = ((int)rint(height * is->aspect_ratio)) & ~1;
         if (width > is->width) {
             width = is->width;
-            height = ((int)rint(width / aspect_ratio)) & ~1;
+            height = ((int)rint(width / is->aspect_ratio)) & ~1;
         }
         x = (is->width - width) / 2;
         y = (is->height - height) / 2;
@@ -720,7 +911,11 @@ static void video_image_display(VideoState *is)
         rect.y = is->ytop  + y;
         rect.w = width;
         rect.h = height;
+
+        overlay_image_display(is, vp->bmp, &rect);
+
         SDL_DisplayYUVOverlay(vp->bmp, &rect);
+
     }
 }
 
@@ -1090,7 +1285,7 @@ static void video_refresh_timer(void *opaque)
     if (is->video_st) {
 retry:
         if (is->pictq_size == 0) {
-            // nothing to do, no picture to display in the que
+            // nothing to do, no picture to display in the queue
         } else {
             double time = av_gettime() / 1000000.0;
             double next_target;
@@ -1182,6 +1377,12 @@ retry:
             SDL_CondSignal(is->pictq_cond);
             SDL_UnlockMutex(is->pictq_mutex);
         }
+
+        /* overlay may work even if no more video picture to display */
+        if (is->overlay_st) {
+            overlay_image_display(is, NULL, NULL);
+        }
+
     } else if (is->audio_st) {
         /* draw the next audio frame */
 
@@ -1195,7 +1396,7 @@ retry:
     if (show_status) {
         static int64_t last_time;
         int64_t cur_time;
-        int aqsize, vqsize, sqsize;
+        int aqsize, vqsize, sqsize, oqsize;
         double av_diff;
 
         cur_time = av_gettime();
@@ -1203,18 +1404,21 @@ retry:
             aqsize = 0;
             vqsize = 0;
             sqsize = 0;
+            oqsize = 0;
             if (is->audio_st)
                 aqsize = is->audioq.size;
             if (is->video_st)
                 vqsize = is->videoq.size;
             if (is->subtitle_st)
                 sqsize = is->subtitleq.size;
+            if (is->overlay_st)
+                oqsize = is->overlayq.size;
             av_diff = 0;
             if (is->audio_st && is->video_st)
                 av_diff = get_audio_clock(is) - get_video_clock(is);
-            printf("%7.2f A-V:%7.3f s:%3.1f aq=%5dKB vq=%5dKB sq=%5dB f=%"PRId64"/%"PRId64"   \r",
+            printf("%7.2f A-V:%7.3f s:%3.1f aq=%5dKB vq=%5dKB sq=%5dB oq=%5dB f=%"PRId64"/%"PRId64"   \r",
                    get_master_clock(is), av_diff, FFMAX(is->skip_frames - 1, 0), aqsize / 1024,
-                   vqsize / 1024, sqsize, is->pts_ctx.num_faulty_dts, is->pts_ctx.num_faulty_pts);
+                   vqsize / 1024, sqsize, oqsize, is->pts_ctx.num_faulty_dts, is->pts_ctx.num_faulty_pts);
             fflush(stdout);
             last_time = cur_time;
         }
@@ -1248,6 +1452,12 @@ static void stream_close(VideoState *is)
     SDL_DestroyCond(is->pictq_cond);
     SDL_DestroyMutex(is->subpq_mutex);
     SDL_DestroyCond(is->subpq_cond);
+    SDL_DestroyMutex(is->ovepq_mutex);
+    SDL_DestroyCond(is->ovepq_cond);
+    if (is->overlay_bmp) {
+        SDL_FreeYUVOverlay(is->overlay_bmp);
+        is->overlay_bmp = NULL;
+    }
 #if !CONFIG_AVFILTER
     if (is->img_convert_ctx)
         sws_freeContext(is->img_convert_ctx);
@@ -1311,6 +1521,20 @@ static void alloc_picture(void *opaque)
         do_exit();
     }
 
+    if (!is->overlay_bmp && is->overlay_stream>=0) {
+        is->overlay_bmp = SDL_CreateYUVOverlay(vp->width, vp->height,
+                                               SDL_YV12_OVERLAY,
+                                               screen);
+        if (!is->overlay_bmp || is->overlay_bmp->pitches[0] < vp->width) {
+            fprintf(stderr, "Error: the video system does not support an image\n"
+                    "size of %dx%d pixels. Try using -vf \"scale=w:h\"\n"
+                    "to reduce the image size.\n", vp->width, vp->height );
+            do_exit();
+        }
+        
+    }
+
+
     SDL_LockMutex(is->pictq_mutex);
     vp->allocated = 1;
     SDL_CondSignal(is->pictq_cond);
@@ -1781,6 +2005,66 @@ static int subtitle_thread(void *arg)
     return 0;
 }
 
+static int overlay_thread(void *arg)
+{
+    VideoState *is = arg;
+    OverlayPicture *sp;
+    AVPacket pkt1, *pkt = &pkt1;
+    int got_overlay;
+    double pts;
+    //int i, j;
+    //int r, g, b, y, u, v, a;
+
+    for (;;) {
+        while (is->paused && !is->overlayq.abort_request) {
+            SDL_Delay(10);
+        }
+        if (packet_queue_get(&is->overlayq, pkt, 1) < 0)
+            break;
+
+        if (pkt->data == flush_pkt.data) {
+            avcodec_flush_buffers(is->overlay_st->codec);
+            continue;
+        }
+        SDL_LockMutex(is->ovepq_mutex);
+        while (is->ovepq_size >= SUBPICTURE_QUEUE_SIZE &&
+               !is->overlayq.abort_request) {
+            SDL_CondWait(is->ovepq_cond, is->ovepq_mutex);
+        }
+        SDL_UnlockMutex(is->ovepq_mutex);
+
+        if (is->overlayq.abort_request)
+            return 0;
+
+        sp = &is->ovepq[is->ovepq_windex];
+        
+       /* NOTE: ipts is the PTS of the _first_ picture beginning in
+           this packet, if any */
+        pts = 0;
+        if (pkt->pts != AV_NOPTS_VALUE)
+            pts = av_q2d(is->overlay_st->time_base) * pkt->pts;
+
+        avcodec_decode_overlay2(is->overlay_st->codec, &sp->overlay,
+                                 &got_overlay, pkt);
+
+        if (got_overlay && sp->overlay.format == 0) {
+            sp->pts = pts;
+            /* now we can update the picture count */
+            if (++is->ovepq_windex == SUBPICTURE_QUEUE_SIZE)
+                is->ovepq_windex = 0;
+
+            SDL_LockMutex(is->ovepq_mutex);
+            is->ovepq_size++;
+            SDL_UnlockMutex(is->ovepq_mutex);
+
+            /* TODO: if got overlay with extra data, may be we want to execute
+               these commands within an HDMV virtual machine */
+        }
+        av_free_packet(pkt);
+    }
+    return 0;
+}
+
 /* copy samples for viewing in editor window */
 static void update_sample_display(VideoState *is, short *samples, int samples_size)
 {
@@ -2071,17 +2355,22 @@ static void sdl_audio_callback(void *opaque, Uint8 *stream, int len)
 static int stream_component_open(VideoState *is, int stream_index)
 {
     AVFormatContext *ic = is->ic;
+    AVFormatContext *sc = is->overlay_ic;
     AVCodecContext *avctx;
     AVCodec *codec;
+    AVStream *stream;
     SDL_AudioSpec wanted_spec, spec;
     AVDictionary *opts;
     AVDictionaryEntry *t = NULL;
 
-    if (stream_index < 0 || stream_index >= ic->nb_streams)
+    if (stream_index < 0 || stream_index >= (ic->nb_streams + (sc?sc->nb_streams:0)))
         return -1;
-    avctx = ic->streams[stream_index]->codec;
-
-    opts = filter_codec_opts(codec_opts, avctx->codec_id, ic, ic->streams[stream_index]);
+    if (stream_index >= ic->nb_streams)
+        stream = sc->streams[stream_index-ic->nb_streams];
+    else
+        stream = ic->streams[stream_index];
+    avctx = stream->codec;
+    opts = filter_codec_opts(codec_opts, avctx->codec_id, (stream_index>=ic->nb_streams ? sc : ic), stream);
 
     codec = avcodec_find_decoder(avctx->codec_id);
     avctx->debug_mv          = debug_mv;
@@ -2137,11 +2426,12 @@ static int stream_component_open(VideoState *is, int stream_index)
         is->resample_channel_layout = is->sdl_channel_layout;
     }
 
-    ic->streams[stream_index]->discard = AVDISCARD_DEFAULT;
+    stream->discard = AVDISCARD_DEFAULT;
+
     switch (avctx->codec_type) {
     case AVMEDIA_TYPE_AUDIO:
         is->audio_stream = stream_index;
-        is->audio_st = ic->streams[stream_index];
+        is->audio_st = stream;
         is->audio_buf_size  = 0;
         is->audio_buf_index = 0;
 
@@ -2158,18 +2448,22 @@ static int stream_component_open(VideoState *is, int stream_index)
         break;
     case AVMEDIA_TYPE_VIDEO:
         is->video_stream = stream_index;
-        is->video_st = ic->streams[stream_index];
-
+        is->video_st = stream;
         packet_queue_init(&is->videoq);
         is->video_tid = SDL_CreateThread(video_thread, is);
         break;
     case AVMEDIA_TYPE_SUBTITLE:
         is->subtitle_stream = stream_index;
-        is->subtitle_st = ic->streams[stream_index];
+        is->subtitle_st = stream;
         packet_queue_init(&is->subtitleq);
-
         is->subtitle_tid = SDL_CreateThread(subtitle_thread, is);
         break;
+    case AVMEDIA_TYPE_OVERLAY:
+        is->overlay_stream = stream_index;
+        is->overlay_st = stream;
+        packet_queue_init(&is->overlayq);
+        is->overlay_tid = SDL_CreateThread(overlay_thread, is);
+        break;
     default:
         break;
     }
@@ -2179,11 +2473,18 @@ static int stream_component_open(VideoState *is, int stream_index)
 static void stream_component_close(VideoState *is, int stream_index)
 {
     AVFormatContext *ic = is->ic;
+    AVFormatContext *sc = is->overlay_ic;
     AVCodecContext *avctx;
+    AVStream *stream;
 
-    if (stream_index < 0 || stream_index >= ic->nb_streams)
+    if (stream_index < 0 || stream_index >= (ic->nb_streams + (sc?sc->nb_streams:0)))
         return;
-    avctx = ic->streams[stream_index]->codec;
+    if (stream_index >= ic->nb_streams)
+        stream = sc->streams[stream_index-ic->nb_streams];
+    else
+        stream = ic->streams[stream_index];
+
+    avctx = stream->codec;
 
     switch (avctx->codec_type) {
     case AVMEDIA_TYPE_AUDIO:
@@ -2234,11 +2535,26 @@ static void stream_component_close(VideoState *is, int stream_index)
 
         packet_queue_end(&is->subtitleq);
         break;
+    case AVMEDIA_TYPE_OVERLAY:
+        packet_queue_abort(&is->overlayq);
+
+        /* note: we also signal this mutex to make sure we deblock the
+           video thread in all cases */
+        SDL_LockMutex(is->ovepq_mutex);
+        is->overlay_stream_changed = 1;
+
+        SDL_CondSignal(is->ovepq_cond);
+        SDL_UnlockMutex(is->ovepq_mutex);
+
+        SDL_WaitThread(is->overlay_tid, NULL);
+
+        packet_queue_end(&is->overlayq);
+        break;
     default:
         break;
     }
 
-    ic->streams[stream_index]->discard = AVDISCARD_ALL;
+    stream->discard = AVDISCARD_ALL;
     avcodec_close(avctx);
     free_buffer_pool(&is->buffer_pool);
     switch (avctx->codec_type) {
@@ -2254,6 +2570,10 @@ static void stream_component_close(VideoState *is, int stream_index)
         is->subtitle_st = NULL;
         is->subtitle_stream = -1;
         break;
+    case AVMEDIA_TYPE_OVERLAY:
+        is->overlay_st = NULL;
+        is->overlay_stream = -1;
+        break;
     default:
         break;
     }
@@ -2273,6 +2593,7 @@ static int decode_thread(void *arg)
 {
     VideoState *is = arg;
     AVFormatContext *ic = NULL;
+    AVFormatContext *sc = NULL;
     int err, i, ret;
     int st_index[AVMEDIA_TYPE_NB];
     AVPacket pkt1, *pkt = &pkt1;
@@ -2286,6 +2607,7 @@ static int decode_thread(void *arg)
     is->video_stream = -1;
     is->audio_stream = -1;
     is->subtitle_stream = -1;
+    is->overlay_stream = -1;
 
     global_video_state = is;
 
@@ -2320,6 +2642,36 @@ static int decode_thread(void *arg)
         av_dict_free(&opts[i]);
     av_freep(&opts);
 
+    if (is->overlay_use_subpath) {
+        sc = avformat_alloc_context();
+        sc->interrupt_callback.callback = decode_interrupt_cb;
+        err = avformat_open_input(&sc, is->overlay_subpath, NULL, &format_opts);
+        if (err < 0) {
+            print_error(is->overlay_subpath, err);
+            ret = -1;
+            goto fail;
+        }
+        if ((t = av_dict_get(format_opts, "", NULL, AV_DICT_IGNORE_SUFFIX))) {
+            av_log(NULL, AV_LOG_ERROR, "Option %s not found.\n", t->key);
+            ret = AVERROR_OPTION_NOT_FOUND;
+            goto fail;
+        }
+        is->overlay_ic = sc;
+        
+        opts = setup_find_stream_info_opts(sc, codec_opts);
+        orig_nb_streams = sc->nb_streams;
+
+        err = avformat_find_stream_info(sc, opts);
+        if (err < 0) {
+            fprintf(stderr, "%s: could not find codec parameters\n", is->filename);
+            ret = -1;
+            goto fail;
+        }
+        for (i = 0; i < orig_nb_streams; i++)
+            av_dict_free(&opts[i]);
+        av_freep(&opts);
+    }
+
     if (ic->pb)
         ic->pb->eof_reached = 0; // FIXME hack, avplay maybe should not use url_feof() to test for the end
 
@@ -2343,6 +2695,10 @@ static int decode_thread(void *arg)
 
     for (i = 0; i < ic->nb_streams; i++)
         ic->streams[i]->discard = AVDISCARD_ALL;
+    if (sc) 
+        for (i = 0; i < sc->nb_streams; i++)
+            sc->streams[i]->discard = AVDISCARD_ALL;
+
     if (!video_disable)
         st_index[AVMEDIA_TYPE_VIDEO] =
             av_find_best_stream(ic, AVMEDIA_TYPE_VIDEO,
@@ -2353,7 +2709,7 @@ static int decode_thread(void *arg)
                                 wanted_stream[AVMEDIA_TYPE_AUDIO],
                                 st_index[AVMEDIA_TYPE_VIDEO],
                                 NULL, 0);
-    if (!video_disable)
+    if (!video_disable) {
         st_index[AVMEDIA_TYPE_SUBTITLE] =
             av_find_best_stream(ic, AVMEDIA_TYPE_SUBTITLE,
                                 wanted_stream[AVMEDIA_TYPE_SUBTITLE],
@@ -2361,8 +2717,35 @@ static int decode_thread(void *arg)
                                  st_index[AVMEDIA_TYPE_AUDIO] :
                                  st_index[AVMEDIA_TYPE_VIDEO]),
                                 NULL, 0);
+        if (!is->overlay_use_subpath) {
+            st_index[AVMEDIA_TYPE_OVERLAY] =
+                av_find_best_stream(ic, AVMEDIA_TYPE_OVERLAY,
+                                    wanted_stream[AVMEDIA_TYPE_OVERLAY],
+                                    (st_index[AVMEDIA_TYPE_AUDIO] >= 0 ?
+                                     st_index[AVMEDIA_TYPE_AUDIO] :
+                                     st_index[AVMEDIA_TYPE_VIDEO]),
+                                    NULL, 0);
+        }
+        else {
+            st_index[AVMEDIA_TYPE_OVERLAY] =
+                av_find_best_stream(sc, AVMEDIA_TYPE_OVERLAY,
+                                    wanted_stream[AVMEDIA_TYPE_OVERLAY],
+                                    (st_index[AVMEDIA_TYPE_AUDIO] >= 0 ?
+                                     st_index[AVMEDIA_TYPE_AUDIO] :
+                                     st_index[AVMEDIA_TYPE_VIDEO]),
+                                    NULL, 0);
+            // found one, adjust index
+            if (st_index[AVMEDIA_TYPE_OVERLAY] >= 0) {
+                st_index[AVMEDIA_TYPE_OVERLAY] += ic->nb_streams;
+            }
+        }
+    }
+    
     if (show_status) {
         av_dump_format(ic, 0, is->filename, 0);
+        if (is->overlay_use_subpath) {
+            av_dump_format(sc, 1, is->overlay_subpath, 0);
+        }
     }
 
     /* open the streams */
@@ -2384,6 +2767,10 @@ static int decode_thread(void *arg)
         stream_component_open(is, st_index[AVMEDIA_TYPE_SUBTITLE]);
     }
 
+    if (st_index[AVMEDIA_TYPE_OVERLAY] >= 0) {
+        stream_component_open(is, st_index[AVMEDIA_TYPE_OVERLAY]);
+    }
+
     if (is->video_stream < 0 && is->audio_stream < 0) {
         fprintf(stderr, "%s: could not open codecs\n", is->filename);
         ret = -1;
@@ -2419,6 +2806,13 @@ static int decode_thread(void *arg)
             if (ret < 0) {
                 fprintf(stderr, "%s: error while seeking\n", is->ic->filename);
             } else {
+                if (is->overlay_ic) {
+                    // also seek subpath if 
+                    ret = avformat_seek_file(is->overlay_ic, -1, seek_min, seek_target, seek_max, is->seek_flags);
+                    if (ret < 0) {
+                        fprintf(stderr, "%s: error while seeking\n", is->ic->filename);
+                    }
+                }
                 if (is->audio_stream >= 0) {
                     packet_queue_flush(&is->audioq);
                     packet_queue_put(&is->audioq, &flush_pkt);
@@ -2427,20 +2821,26 @@ static int decode_thread(void *arg)
                     packet_queue_flush(&is->subtitleq);
                     packet_queue_put(&is->subtitleq, &flush_pkt);
                 }
+                if (is->overlay_stream >= 0) {
+                    packet_queue_flush(&is->overlayq);
+                    packet_queue_put(&is->overlayq, &flush_pkt);
+                }
                 if (is->video_stream >= 0) {
                     packet_queue_flush(&is->videoq);
                     packet_queue_put(&is->videoq, &flush_pkt);
                 }
             }
+
             is->seek_req = 0;
             eof = 0;
         }
 
         /* if the queue are full, no need to read more */
-        if (   is->audioq.size + is->videoq.size + is->subtitleq.size > MAX_QUEUE_SIZE
+        if (   is->audioq.size + is->videoq.size + is->subtitleq.size + is->overlayq.size > MAX_QUEUE_SIZE
             || (   (is->audioq   .size  > MIN_AUDIOQ_SIZE || is->audio_stream < 0)
                 && (is->videoq   .nb_packets > MIN_FRAMES || is->video_stream < 0)
-                && (is->subtitleq.nb_packets > MIN_FRAMES || is->subtitle_stream < 0))) {
+                && (is->subtitleq.nb_packets > MIN_FRAMES || is->subtitle_stream < 0)
+                && (is->overlayq.nb_packets > MIN_FRAMES || is->overlay_stream < 0))) {
             /* wait 10 ms */
             SDL_Delay(10);
             continue;
@@ -2462,7 +2862,7 @@ static int decode_thread(void *arg)
                 packet_queue_put(&is->audioq, pkt);
             }
             SDL_Delay(10);
-            if (is->audioq.size + is->videoq.size + is->subtitleq.size == 0) {
+            if (is->audioq.size + is->videoq.size + is->subtitleq.size + is->overlayq.size == 0) {
                 if (loop != 1 && (!loop || --loop)) {
                     stream_seek(cur_stream, start_time != AV_NOPTS_VALUE ? start_time : 0, 0, 0);
                 } else if (autoexit) {
@@ -2493,9 +2893,33 @@ static int decode_thread(void *arg)
             packet_queue_put(&is->videoq, pkt);
         } else if (pkt->stream_index == is->subtitle_stream && pkt_in_play_range) {
             packet_queue_put(&is->subtitleq, pkt);
+        } else if (pkt->stream_index == is->overlay_stream && pkt_in_play_range) {
+            packet_queue_put(&is->overlayq, pkt);
         } else {
             av_free_packet(pkt);
         }
+
+        if (is->overlay_ic) {
+            ret = av_read_frame(is->overlay_ic, pkt);
+            if (ret < 0) {
+                if (is->overlay_ic->pb && is->overlay_ic->pb->error)
+                    break;
+                continue;
+            }
+            /* check if packet is in play range specified by user, then queue, otherwise discard */
+            pkt_in_play_range = duration == AV_NOPTS_VALUE ||
+                (pkt->pts - ic->streams[pkt->stream_index]->start_time) *
+                av_q2d(ic->streams[pkt->stream_index]->time_base) -
+                (double)(start_time != AV_NOPTS_VALUE ? start_time : 0) / 1000000
+                <= ((double)duration / 1000000);
+            if (pkt->stream_index == (is->subtitle_stream-ic->nb_streams) && pkt_in_play_range) {
+                packet_queue_put(&is->subtitleq, pkt);
+            } else if (pkt->stream_index == (is->overlay_stream-ic->nb_streams) && pkt_in_play_range) {
+                packet_queue_put(&is->overlayq, pkt);
+            } else {
+                av_free_packet(pkt);
+            }
+        }
     }
     /* wait until the end */
     while (!is->abort_request) {
@@ -2514,9 +2938,14 @@ static int decode_thread(void *arg)
         stream_component_close(is, is->video_stream);
     if (is->subtitle_stream >= 0)
         stream_component_close(is, is->subtitle_stream);
+    if (is->overlay_stream >= 0)
+        stream_component_close(is, is->overlay_stream);
     if (is->ic) {
         avformat_close_input(&is->ic);
     }
+    if (is->overlay_ic) {
+        avformat_close_input(&is->overlay_ic);
+    }
 
     if (ret != 0) {
         SDL_Event event;
@@ -2528,7 +2957,7 @@ static int decode_thread(void *arg)
     return 0;
 }
 
-static VideoState *stream_open(const char *filename, AVInputFormat *iformat)
+static VideoState *stream_open(const char *filename, const char *subpath, AVInputFormat *iformat)
 {
     VideoState *is;
 
@@ -2536,6 +2965,10 @@ static VideoState *stream_open(const char *filename, AVInputFormat *iformat)
     if (!is)
         return NULL;
     av_strlcpy(is->filename, filename, sizeof(is->filename));
+    if (subpath) {
+        av_strlcpy(is->overlay_subpath, subpath, sizeof(is->overlay_subpath));
+        is->overlay_use_subpath = 1;
+    }
     is->iformat = iformat;
     is->ytop    = 0;
     is->xleft   = 0;
@@ -2547,6 +2980,9 @@ static VideoState *stream_open(const char *filename, AVInputFormat *iformat)
     is->subpq_mutex = SDL_CreateMutex();
     is->subpq_cond  = SDL_CreateCond();
 
+    is->ovepq_mutex = SDL_CreateMutex();
+    is->ovepq_cond  = SDL_CreateCond();
+
     is->av_sync_type = av_sync_type;
     is->parse_tid    = SDL_CreateThread(decode_thread, is);
     if (!is->parse_tid) {
@@ -2556,6 +2992,34 @@ static VideoState *stream_open(const char *filename, AVInputFormat *iformat)
     return is;
 }
 
+static void stream_handle_event(VideoState *is, SDL_Event *event)
+{
+    AVPacket pkt1, *pkt = &pkt1;
+    char key = 0;
+    if (event != NULL && event->type == SDL_KEYDOWN) switch(event->key.keysym.sym) {
+        case SDLK_RETURN: key =  13; break; // activate current button
+        case SDLK_u:      key = 'u'; break; // up
+        case SDLK_d:      key = 'd'; break; // down
+        case SDLK_l:      key = 'l'; break; // left
+        case SDLK_r:      key = 'r'; break; // right
+        case SDLK_p:      key = 'p'; break; // roll pages
+        }
+
+    //pass key to decoder using a fake packet
+    if (is->overlay_stream >= 0) {
+        av_init_packet(pkt);
+        pkt->size = (key != 0 ? 4 : 3);
+        pkt->data = av_mallocz(pkt->size);
+        *(pkt->data)   = 0x80;
+        *(pkt->data+1) = 0x00;
+        *(pkt->data+2) = (key != 0 ? 1 : 0);
+        if (key != 0)
+            *(char*)(pkt->data+3) = key;
+        pkt->stream_index = is->overlay_stream;
+        packet_queue_put(&is->overlayq, pkt);
+    }
+}
+
 static void stream_cycle_channel(VideoState *is, int codec_type)
 {
     AVFormatContext *ic = is->ic;
@@ -2566,15 +3030,17 @@ static void stream_cycle_channel(VideoState *is, int codec_type)
         start_index = is->video_stream;
     else if (codec_type == AVMEDIA_TYPE_AUDIO)
         start_index = is->audio_stream;
-    else
+    else if (codec_type == AVMEDIA_TYPE_SUBTITLE)
         start_index = is->subtitle_stream;
-    if (start_index < (codec_type == AVMEDIA_TYPE_SUBTITLE ? -1 : 0))
+    else 
+        start_index = is->overlay_stream;
+    if (start_index < (codec_type == AVMEDIA_TYPE_SUBTITLE || codec_type == AVMEDIA_TYPE_OVERLAY ? -1 : 0))
         return;
     stream_index = start_index;
     for (;;) {
         if (++stream_index >= is->ic->nb_streams)
         {
-            if (codec_type == AVMEDIA_TYPE_SUBTITLE)
+            if (codec_type == AVMEDIA_TYPE_SUBTITLE || codec_type == AVMEDIA_TYPE_OVERLAY)
             {
                 stream_index = -1;
                 goto the_end;
@@ -2594,6 +3060,7 @@ static void stream_cycle_channel(VideoState *is, int codec_type)
                 break;
             case AVMEDIA_TYPE_VIDEO:
             case AVMEDIA_TYPE_SUBTITLE:
+            case AVMEDIA_TYPE_OVERLAY:
                 goto the_end;
             default:
                 break;
@@ -2670,7 +3137,6 @@ static void event_loop(void)
             case SDLK_f:
                 toggle_full_screen();
                 break;
-            case SDLK_p:
             case SDLK_SPACE:
                 toggle_pause();
                 break;
@@ -2689,6 +3155,20 @@ static void event_loop(void)
                 if (cur_stream)
                     stream_cycle_channel(cur_stream, AVMEDIA_TYPE_SUBTITLE);
                 break;
+            case SDLK_o:
+                if (cur_stream)
+                    stream_cycle_channel(cur_stream, AVMEDIA_TYPE_OVERLAY);
+                break;
+            case SDLK_RETURN:
+            case SDLK_u:
+            case SDLK_d:
+            case SDLK_l:
+            case SDLK_r:
+            case SDLK_p:
+                if (cur_stream)
+                    stream_handle_event(cur_stream, &event);
+                break;
+
             case SDLK_w:
                 toggle_audio_display();
                 break;
@@ -2939,24 +3419,35 @@ static void show_help(void)
     printf("\nWhile playing:\n"
            "q, ESC              quit\n"
            "f                   toggle full screen\n"
-           "p, SPC              pause\n"
+           "SPC                 pause\n"
            "a                   cycle audio channel\n"
            "v                   cycle video channel\n"
            "t                   cycle subtitle channel\n"
+           "o                   cycle overlay channel\n"
            "w                   show audio waves\n"
            "s                   activate frame-step mode\n"
            "left/right          seek backward/forward 10 seconds\n"
            "down/up             seek backward/forward 1 minute\n"
            "mouse click         seek to percentage in file corresponding to fraction of width\n"
+           "u                   navigate 'up' in overlay\n"
+           "d                   navigate 'down' in overlay\n"
+           "l                   navigate 'left' in overlay\n"
+           "r                   navigate 'right' in overlay\n"
+           "ENTER               activate selected overlay button\n"
+           "p                   toggle overlay display (popup menu)\n"
            );
 }
 
 static void opt_input_file(void *optctx, const char *filename)
 {
     if (input_filename) {
-        fprintf(stderr, "Argument '%s' provided as input filename, but '%s' was already specified.\n",
-                filename, input_filename);
-        exit(1);
+        if (subpath_filename) {
+            fprintf(stderr, "Argument '%s' provided as subpath filename, but '%s' was already specified.\n",
+                    filename, subpath_filename);
+            exit(1);
+        }
+        subpath_filename = filename;
+        return;
     }
     if (!strcmp(filename, "-"))
         filename = "pipe:";
@@ -3022,7 +3513,7 @@ int main(int argc, char **argv)
     av_init_packet(&flush_pkt);
     flush_pkt.data = "FLUSH";
 
-    cur_stream = stream_open(input_filename, file_iformat);
+    cur_stream = stream_open(input_filename, subpath_filename, file_iformat);
 
     event_loop();
 
-- 
1.7.9.5

