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Diffstat (limited to 'libavformat/rtpenc_h263_rfc2190.c')
-rw-r--r--libavformat/rtpenc_h263_rfc2190.c104
1 files changed, 104 insertions, 0 deletions
diff --git a/libavformat/rtpenc_h263_rfc2190.c b/libavformat/rtpenc_h263_rfc2190.c
new file mode 100644
index 0000000000..305c1a27c8
--- /dev/null
+++ b/libavformat/rtpenc_h263_rfc2190.c
@@ -0,0 +1,104 @@
+/*
+ * RTP packetization for H.263 video
+ * Copyright (c) 2012 Martin Storsjo
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "avformat.h"
+#include "rtpenc.h"
+#include "libavcodec/put_bits.h"
+#include "libavcodec/get_bits.h"
+
+struct H263Info {
+ int src;
+ int i;
+ int u;
+ int s;
+ int a;
+ int pb;
+ int tr;
+};
+
+static void send_mode_a(AVFormatContext *s1, const struct H263Info *info,
+ const uint8_t *buf, int len, int m)
+{
+ RTPMuxContext *s = s1->priv_data;
+ PutBitContext pb;
+
+ init_put_bits(&pb, s->buf, 32);
+ put_bits(&pb, 1, 0); /* F - 0, mode A */
+ put_bits(&pb, 1, 0); /* P - 0, normal I/P */
+ put_bits(&pb, 3, 0); /* SBIT - 0 bits */
+ put_bits(&pb, 3, 0); /* EBIT - 0 bits */
+ put_bits(&pb, 3, info->src); /* SRC - source format */
+ put_bits(&pb, 1, info->i); /* I - inter/intra */
+ put_bits(&pb, 1, info->u); /* U - unrestricted motion vector */
+ put_bits(&pb, 1, info->s); /* S - syntax-baesd arithmetic coding */
+ put_bits(&pb, 1, info->a); /* A - advanced prediction */
+ put_bits(&pb, 4, 0); /* R - reserved */
+ put_bits(&pb, 2, 0); /* DBQ - 0 */
+ put_bits(&pb, 3, 0); /* TRB - 0 */
+ put_bits(&pb, 8, info->tr); /* TR */
+ flush_put_bits(&pb);
+ memcpy(s->buf + 4, buf, len);
+
+ ff_rtp_send_data(s1, s->buf, len + 4, m);
+}
+
+void ff_rtp_send_h263_rfc2190(AVFormatContext *s1, const uint8_t *buf, int size)
+{
+ RTPMuxContext *s = s1->priv_data;
+ int len;
+ GetBitContext gb;
+ struct H263Info info = { 0 };
+
+ s->timestamp = s->cur_timestamp;
+
+ init_get_bits(&gb, buf, size*8);
+ if (get_bits(&gb, 22) == 0x20) { /* Picture Start Code */
+ info.tr = get_bits(&gb, 8);
+ skip_bits(&gb, 2); /* PTYPE start, H261 disambiguation */
+ skip_bits(&gb, 3); /* Split screen, document camera, freeze picture release */
+ info.src = get_bits(&gb, 3);
+ info.i = get_bits(&gb, 1);
+ info.u = get_bits(&gb, 1);
+ info.s = get_bits(&gb, 1);
+ info.a = get_bits(&gb, 1);
+ info.pb = get_bits(&gb, 1);
+ }
+
+ while (size > 0) {
+ len = FFMIN(s->max_payload_size - 4, size);
+
+ /* Look for a better place to split the frame into packets. */
+ if (len < size) {
+ const uint8_t *end = ff_h263_find_resync_marker_reverse(buf,
+ buf + len);
+ len = end - buf;
+ if (len == s->max_payload_size - 4)
+ av_log(s1, AV_LOG_WARNING,
+ "No GOB boundary found within MTU size, splitting at "
+ "a random boundary\n");
+ }
+
+ send_mode_a(s1, &info, buf, len, len == size);
+
+ buf += len;
+ size -= len;
+ }
+}