Silicon Graphics Movie demuxer

[ffmpeg] / libavformat / rtpdec_vp8.c

diff --git a/libavformat/rtpdec_vp8.c b/libavformat/rtpdec_vp8.c
index 966f7b87342393c27056486f06bf444f05d11ac0..fc86ac1dd3b5d078f92ae9657151788e54a2f3ee 100644 (file)
--- a/libavformat/rtpdec_vp8.c
+++ b/libavformat/rtpdec_vp8.c
@@ -35,11 +35,21 @@ struct PayloadContext {
     AVIOContext *data;
     uint32_t     timestamp;
     int          is_keyframe;
+    /* If sequence_ok is set, we keep returning data (even if we might have
+     * lost some data, but we haven't lost any too critical data that would
+     * cause the decoder to desynchronize and output random garbage).
+     */
     int          sequence_ok;
     int          first_part_size;
     uint16_t     prev_seq;
     int          prev_pictureid;
     int          broken_frame;
+    /* If sequence_dirty is set, we have lost some data (critical or
+     * non-critical) and decoding will have some sort of artefacts, and
+     * we thus should request a new keyframe.
+     */
+    int          sequence_dirty;
+    int          got_keyframe;
 };
 
 static void vp8_free_buffer(PayloadContext *vp8)
@@ -70,9 +80,9 @@ static int vp8_handle_packet(AVFormatContext *ctx, PayloadContext *vp8,
     int extended_bits, part_id;
     int pictureid_present = 0, tl0picidx_present = 0, tid_present = 0,
         keyidx_present = 0;
-    int pictureid = -1, pictureid_mask;
+    int pictureid = -1, pictureid_mask = 0;
     int returned_old_frame = 0;
-    uint32_t old_timestamp;
+    uint32_t old_timestamp = 0;
 
     if (!buf) {
         if (vp8->data) {
@@ -80,6 +90,8 @@ static int vp8_handle_packet(AVFormatContext *ctx, PayloadContext *vp8,
             if (ret < 0)
                 return ret;
             *timestamp = vp8->timestamp;
+            if (vp8->sequence_dirty)
+                pkt->flags |= AV_PKT_FLAG_CORRUPT;
             return 0;
         }
         return AVERROR(EAGAIN);
@@ -141,11 +153,15 @@ static int vp8_handle_packet(AVFormatContext *ctx, PayloadContext *vp8,
             vp8_free_buffer(vp8);
             // Keyframe, decoding ok again
             vp8->sequence_ok = 1;
+            vp8->sequence_dirty = 0;
+            vp8->got_keyframe = 1;
         } else {
             int can_continue = vp8->data && !vp8->is_keyframe &&
                                avio_tell(vp8->data) >= vp8->first_part_size;
             if (!vp8->sequence_ok)
                 return AVERROR(EAGAIN);
+            if (!vp8->got_keyframe)
+                return vp8_broken_sequence(ctx, vp8, "Keyframe missing\n");
             if (pictureid >= 0) {
                 if (pictureid != ((vp8->prev_pictureid + 1) & pictureid_mask)) {
                     return vp8_broken_sequence(ctx, vp8,
@@ -179,11 +195,12 @@ static int vp8_handle_packet(AVFormatContext *ctx, PayloadContext *vp8,
                 }
             }
             if (vp8->data) {
+                vp8->sequence_dirty = 1;
                 if (avio_tell(vp8->data) >= vp8->first_part_size) {
                     int ret = ff_rtp_finalize_packet(pkt, &vp8->data, st->index);
                     if (ret < 0)
                         return ret;
-                    pkt->size = vp8->first_part_size;
+                    pkt->flags |= AV_PKT_FLAG_CORRUPT;
                     returned_old_frame = 1;
                     old_timestamp = vp8->timestamp;
                 } else {
@@ -207,11 +224,8 @@ static int vp8_handle_packet(AVFormatContext *ctx, PayloadContext *vp8,
 
         if (vp8->timestamp != *timestamp) {
             // Missed the start of the new frame, sequence broken
-            vp8->sequence_ok = 0;
-            av_log(ctx, AV_LOG_WARNING,
-                   "Received no start marker; dropping frame\n");
-            vp8_free_buffer(vp8);
-            return AVERROR(EAGAIN);
+            return vp8_broken_sequence(ctx, vp8,
+                                       "Received no start marker; dropping frame\n");
         }
 
         if (seq != expected_seq) {
@@ -220,6 +234,7 @@ static int vp8_handle_packet(AVFormatContext *ctx, PayloadContext *vp8,
                                            "Missed part of a keyframe, sequence broken\n");
             } else if (vp8->data && avio_tell(vp8->data) >= vp8->first_part_size) {
                 vp8->broken_frame = 1;
+                vp8->sequence_dirty = 1;
             } else {
                 return vp8_broken_sequence(ctx, vp8,
                                            "Missed part of the first partition, sequence broken\n");
@@ -231,7 +246,8 @@ static int vp8_handle_packet(AVFormatContext *ctx, PayloadContext *vp8,
         return vp8_broken_sequence(ctx, vp8, "Received no start marker\n");
 
     vp8->prev_seq = seq;
-    avio_write(vp8->data, buf, len);
+    if (!vp8->broken_frame)
+        avio_write(vp8->data, buf, len);
 
     if (returned_old_frame) {
         *timestamp = old_timestamp;
@@ -243,8 +259,8 @@ static int vp8_handle_packet(AVFormatContext *ctx, PayloadContext *vp8,
         ret = ff_rtp_finalize_packet(pkt, &vp8->data, st->index);
         if (ret < 0)
             return ret;
-        if (vp8->broken_frame)
-            pkt->size = vp8->first_part_size;
+        if (vp8->sequence_dirty)
+            pkt->flags |= AV_PKT_FLAG_CORRUPT;
         return 0;
     }
 
@@ -253,7 +269,11 @@ static int vp8_handle_packet(AVFormatContext *ctx, PayloadContext *vp8,
 
 static PayloadContext *vp8_new_context(void)
 {
-    return av_mallocz(sizeof(PayloadContext));
+    PayloadContext *vp8 = av_mallocz(sizeof(PayloadContext));
+    if (!vp8)
+        return NULL;
+    vp8->sequence_ok = 1;
+    return vp8;
 }
 
 static void vp8_free_context(PayloadContext *vp8)
@@ -262,6 +282,11 @@ static void vp8_free_context(PayloadContext *vp8)
     av_free(vp8);
 }
 
+static int vp8_need_keyframe(PayloadContext *vp8)
+{
+    return vp8->sequence_dirty || !vp8->sequence_ok;
+}
+
 RTPDynamicProtocolHandler ff_vp8_dynamic_handler = {
     .enc_name       = "VP8",
     .codec_type     = AVMEDIA_TYPE_VIDEO,
@@ -269,4 +294,5 @@ RTPDynamicProtocolHandler ff_vp8_dynamic_handler = {
     .alloc          = vp8_new_context,
     .free           = vp8_free_context,
     .parse_packet   = vp8_handle_packet,
+    .need_keyframe  = vp8_need_keyframe,
 };