examples/decode_video: allocate the packet dynamically

AVPackets on stack are discouraged.

doc/examples/decode_video.c

@@ -94,7 +94,7 @@ int main(int argc, char **argv)
     uint8_t *data;
     size_t   data_size;
     int ret;
-    AVPacket avpkt;
+    AVPacket *pkt;
 
     if (argc <= 2) {
         fprintf(stderr, "Usage: %s <input file> <output file>\n", argv[0]);
@@ -105,7 +105,9 @@ int main(int argc, char **argv)
 
     avcodec_register_all();
 
-    av_init_packet(&avpkt);
+    pkt = av_packet_alloc();
+    if (!pkt)
+        exit(1);
 
     /* set end of buffer to 0 (this ensures that no overreading happens for damaged MPEG streams) */
     memset(inbuf + INBUF_SIZE, 0, AV_INPUT_BUFFER_PADDING_SIZE);
@@ -151,7 +153,7 @@ int main(int argc, char **argv)
         /* use the parser to split the data into frames */
         data = inbuf;
         while (data_size > 0) {
-            ret = av_parser_parse2(parser, c, &avpkt.data, &avpkt.size,
+            ret = av_parser_parse2(parser, c, &pkt->data, &pkt->size,
                                    data, data_size, AV_NOPTS_VALUE, AV_NOPTS_VALUE, 0);
             if (ret < 0) {
                 fprintf(stderr, "Error while parsing\n");
@@ -160,8 +162,8 @@ int main(int argc, char **argv)
             data      += ret;
             data_size -= ret;
 
-            if (avpkt.size)
-                decode(c, picture, &avpkt, outfilename);
+            if (pkt->size)
+                decode(c, picture, pkt, outfilename);
         }
     }
 
@@ -173,6 +175,7 @@ int main(int argc, char **argv)
     av_parser_close(parser);
     avcodec_free_context(&c);
     av_frame_free(&picture);
+    av_packet_free(&pkt);
 
     return 0;
 }