rtmppkt: Rename the ts_delta field to ts_field

Based on a suggestion by Martin Panter. This is more descriptive,
since it's the actual timestamp field from the RTMP packet,
which might or might not be a delta depending on context (in
some packets it's a delta, in some packets it's an absolute
timestamp, and in some packets it's 0xffffff to indicate that
the actual delta or absolute timestamp is transmitted separately).
Signed-off-by: Martin Storsjö <martin@martin.st>

libavformat/rtmppkt.c

@@ -196,7 +196,7 @@ static int rtmp_packet_read_one_chunk(URLContext *h, RTMPPacket *p,
 
     hdr >>= 6; // header size indicator
     if (hdr == RTMP_PS_ONEBYTE) {
-        ts_field = prev_pkt[channel_id].ts_delta;
+        ts_field = prev_pkt[channel_id].ts_field;
     } else {
         if (ffurl_read_complete(h, buf, 3) != 3)
             return AVERROR(EIO);
@@ -235,7 +235,7 @@ static int rtmp_packet_read_one_chunk(URLContext *h, RTMPPacket *p,
             return ret;
         p->read = written;
         p->offset = 0;
-        prev_pkt[channel_id].ts_delta   = ts_field;
+        prev_pkt[channel_id].ts_field   = ts_field;
         prev_pkt[channel_id].timestamp  = timestamp;
     } else {
         // previous packet in this channel hasn't completed reading
@@ -244,7 +244,7 @@ static int rtmp_packet_read_one_chunk(URLContext *h, RTMPPacket *p,
         p->size          = prev->size;
         p->channel_id    = prev->channel_id;
         p->type          = prev->type;
-        p->ts_delta      = prev->ts_delta;
+        p->ts_field      = prev->ts_field;
         p->extra         = prev->extra;
         p->offset        = prev->offset;
         p->read          = prev->read + written;
@@ -323,16 +323,16 @@ int ff_rtmp_packet_write(URLContext *h, RTMPPacket *pkt,
         timestamp -= prev_pkt[pkt->channel_id].timestamp;
     }
     if (timestamp >= 0xFFFFFF) {
-        pkt->ts_delta = 0xFFFFFF;
+        pkt->ts_field = 0xFFFFFF;
     } else {
-        pkt->ts_delta = timestamp;
+        pkt->ts_field = timestamp;
     }
 
     if (use_delta) {
         if (pkt->type == prev_pkt[pkt->channel_id].type &&
             pkt->size == prev_pkt[pkt->channel_id].size) {
             mode = RTMP_PS_FOURBYTES;
-            if (pkt->ts_delta == prev_pkt[pkt->channel_id].ts_delta)
+            if (pkt->ts_field == prev_pkt[pkt->channel_id].ts_field)
                 mode = RTMP_PS_ONEBYTE;
         } else {
             mode = RTMP_PS_EIGHTBYTES;
@@ -349,7 +349,7 @@ int ff_rtmp_packet_write(URLContext *h, RTMPPacket *pkt,
         bytestream_put_le16(&p, pkt->channel_id - 64);
     }
     if (mode != RTMP_PS_ONEBYTE) {
-        bytestream_put_be24(&p, pkt->ts_delta);
+        bytestream_put_be24(&p, pkt->ts_field);
         if (mode != RTMP_PS_FOURBYTES) {
             bytestream_put_be24(&p, pkt->size);
             bytestream_put_byte(&p, pkt->type);
@@ -357,14 +357,14 @@ int ff_rtmp_packet_write(URLContext *h, RTMPPacket *pkt,
                 bytestream_put_le32(&p, pkt->extra);
         }
     }
-    if (pkt->ts_delta == 0xFFFFFF)
+    if (pkt->ts_field == 0xFFFFFF)
         bytestream_put_be32(&p, timestamp);
     // save history
     prev_pkt[pkt->channel_id].channel_id = pkt->channel_id;
     prev_pkt[pkt->channel_id].type       = pkt->type;
     prev_pkt[pkt->channel_id].size       = pkt->size;
     prev_pkt[pkt->channel_id].timestamp  = pkt->timestamp;
-    prev_pkt[pkt->channel_id].ts_delta   = pkt->ts_delta;
+    prev_pkt[pkt->channel_id].ts_field   = pkt->ts_field;
     prev_pkt[pkt->channel_id].extra      = pkt->extra;
 
     if ((ret = ffurl_write(h, pkt_hdr, p - pkt_hdr)) < 0)
@@ -398,7 +398,7 @@ int ff_rtmp_packet_create(RTMPPacket *pkt, int channel_id, RTMPPacketType type,
     pkt->type       = type;
     pkt->timestamp  = timestamp;
     pkt->extra      = 0;
-    pkt->ts_delta   = 0;
+    pkt->ts_field   = 0;
 
     return 0;
 }

libavformat/rtmppkt.h

@@ -78,7 +78,7 @@ typedef struct RTMPPacket {
     int            channel_id; ///< RTMP channel ID (nothing to do with audio/video channels though)
     RTMPPacketType type;       ///< packet payload type
     uint32_t       timestamp;  ///< packet full timestamp
-    uint32_t       ts_delta;   ///< 24-bit timestamp or increment to the previous one, in milliseconds (latter only for media packets). Clipped to a maximum of 0xFFFFFF, indicating an extended timestamp field.
+    uint32_t       ts_field;   ///< 24-bit timestamp or increment to the previous one, in milliseconds (latter only for media packets). Clipped to a maximum of 0xFFFFFF, indicating an extended timestamp field.
     uint32_t       extra;      ///< probably an additional channel ID used during streaming data
     uint8_t        *data;      ///< packet payload
     int            size;       ///< packet payload size