avformat/rtsp: move SDP_MAX_SIZE macro definition to header file

move comments for the size of SDP_MAX_SIZE here:
Some SDP lines, particularly for Realmedia or ASF RTSP streams,
contain long SDP lines containing complete ASF Headers (several
kB) or arrays of MDPR (RM stream descriptor) headers plus
"rulebooks" describing their properties. Therefore, the SDP line
buffer is large.
The Vorbis FMTP line can be up to 16KB - see xiph_parse_sdp_line
in rtpdec_xiph.c.

Signed-off-by: Limin Wang <lance.lmwang@gmail.com>

libavformat/rtsp.c

@@ -53,7 +53,6 @@
 
 /* Default timeout values for read packet in seconds  */
 #define READ_PACKET_TIMEOUT_S 10
-#define SDP_MAX_SIZE 16384
 #define RECVBUF_SIZE 10 * RTP_MAX_PACKET_LENGTH
 #define DEFAULT_REORDERING_DELAY 100000
 
@@ -688,14 +687,6 @@ int ff_sdp_parse(AVFormatContext *s, const char *content)
 {
     const char *p;
     int letter, i;
-    /* Some SDP lines, particularly for Realmedia or ASF RTSP streams,
-     * contain long SDP lines containing complete ASF Headers (several
-     * kB) or arrays of MDPR (RM stream descriptor) headers plus
-     * "rulebooks" describing their properties. Therefore, the SDP line
-     * buffer is large.
-     *
-     * The Vorbis FMTP line can be up to 16KB - see xiph_parse_sdp_line
-     * in rtpdec_xiph.c. */
     char buf[SDP_MAX_SIZE], *q;
     SDPParseState sdp_parse_state = { { 0 } }, *s1 = &sdp_parse_state;
 

libavformat/rtsp.h

@@ -78,6 +78,7 @@ enum RTSPControlTransport {
 #define RTSP_DEFAULT_AUDIO_SAMPLERATE 44100
 #define RTSP_RTP_PORT_MIN 5000
 #define RTSP_RTP_PORT_MAX 65000
+#define SDP_MAX_SIZE 16384
 
 /**
  * This describes a single item in the "Transport:" line of one stream as

libavformat/rtspenc.c

@@ -34,7 +34,6 @@
 #include "libavutil/time.h"
 #include "url.h"
 
-#define SDP_MAX_SIZE 16384
 
 static const AVClass rtsp_muxer_class = {
     .class_name = "RTSP muxer",