X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=fecdec_filter.c;h=794add49ec42d07c04ea826e36f8f77b80a9dad6;hp=6ca0b037da0f55be826137facc4632415648329c;hb=89e28a4361bd120dfe4202a16d85d03fb1139de8;hpb=30496a3da233a6cfb0b1005b808e8d1064cb91ff

diff --git a/fecdec_filter.c b/fecdec_filter.c
index 6ca0b037..794add49 100644
--- a/fecdec_filter.c
+++ b/fecdec_filter.c
@@ -28,7 +28,7 @@
 #define NUM_FEC_GROUPS 3
 
 /** Size of the output buffer of the fecdec filter. */
-#define FECDEC_OUTBUF_SIZE (128 * 1024)
+#define FECDEC_OUTBUF_SIZE (1024 * 1024) /* FIXME: This has to depend on the fec params */
 
 /** Data read from the header of a slice. */
 struct fec_header {
@@ -46,6 +46,10 @@ struct fec_header {
 	uint8_t slice_num;
 	/** Used data bytes of this slice. */
 	uint16_t slice_bytes;
+	/** Non-zero if this group is the beginning of the stream. */
+	uint8_t bos;
+	/** Non-zero if this stream embedds audio headers into fec groups. */
+	uint8_t header_stream;
 };
 
 /**
@@ -72,6 +76,7 @@ struct private_fecdec_data {
 	struct fec_parms *fec;
 	/** Keeps track of what was received so far. */
 	struct fecdec_group groups[NUM_FEC_GROUPS];
+	int have_header;
 };
 
 /** Iterate over all fecdec groups. */
@@ -198,6 +203,8 @@ static int add_slice(char *buf, struct fecdec_group *fg)
 	int r, slice_num;
 
 	if (group_complete(fg)) {
+		PARA_DEBUG_LOG("group complete, ignoring slice %d\n",
+			fg->h.slice_num);
 		fg->num_received_slices++;
 		return 0;
 	}
@@ -216,19 +223,58 @@ static int add_slice(char *buf, struct fecdec_group *fg)
 	return 1;
 }
 
+enum fec_group_usability {
+	FEC_GROUP_UNUSABLE,
+	FEC_GROUP_USABLE,
+	FEC_GROUP_USABLE_SKIP_HEADER,
+};
+
+static enum fec_group_usability group_is_usable(struct fecdec_group *fg,
+		struct private_fecdec_data *pfd)
+{
+	struct fec_header *h = &fg->h;
+
+	if (!h->header_stream)
+		return FEC_GROUP_USABLE;
+	if (pfd->have_header) {
+		if (h->audio_header_size)
+			return FEC_GROUP_USABLE_SKIP_HEADER;
+		return FEC_GROUP_USABLE;
+	}
+	if (fg->h.bos)
+		return FEC_GROUP_USABLE;
+	if (fg->h.audio_header_size)
+		return FEC_GROUP_USABLE;
+	return FEC_GROUP_UNUSABLE;
+}
+
 static int decode_group(struct fecdec_group *fg, struct filter_node *fn)
 {
 	int i, ret, sb = fg->h.slice_bytes;
 	size_t written = 0;
 	struct private_fecdec_data *pfd = fn->private_data;
+	enum fec_group_usability u = group_is_usable(fg, pfd);
 
+	if (u == FEC_GROUP_UNUSABLE) {
+		PARA_INFO_LOG("dropping unusable group %d\n", fg->h.group_num);
+		return 0;
+	}
+	PARA_DEBUG_LOG("decoding group %d %d slices\n", fg->h.group_num,
+		fg->h.data_slices_per_group);
 	ret = fec_decode(pfd->fec, fg->data, fg->idx, sb);
 	if (ret < 0)
 		return ret;
+	pfd->have_header = 1;
+	i = 0;
+	if (u == FEC_GROUP_USABLE_SKIP_HEADER) {
+		i = ROUND_UP(fg->h.audio_header_size, fg->h.slice_bytes)
+			/ fg->h.slice_bytes;
+		PARA_DEBUG_LOG("skipping %d header slices\n", i);
+	}
 	PARA_DEBUG_LOG("writing group %d (%d/%d decoded data bytes)\n",
 		fg->h.group_num, fg->h.group_bytes,
 		fg->h.data_slices_per_group * sb);
-	for (i = 0; i < fg->h.data_slices_per_group; i++) {
+	for (; i < fg->h.data_slices_per_group; i++) {
 		size_t n = sb;
 		if (n + written > fg->h.group_bytes)
 			n = fg->h.group_bytes - written;
@@ -265,7 +311,9 @@ static int read_fec_header(char *buf, size_t len, struct fec_header *h)
 
 	h->slice_num = read_u8(buf + 18);
 	h->slice_bytes = read_u16(buf + 20);
-	if (!h->group_bytes && & h->slice_bytes)
+	h->bos = read_u8(buf + 22);
+	h->header_stream = read_u8(buf + 23);
+	if (!memcmp(buf, FEC_EOF_PACKET, FEC_EOF_PACKET_LEN))
 		return -E_FECDEC_EOF;
 //	PARA_DEBUG_LOG("group %u, slize %u, slices per group: %u\n",
 //		h->group_num, h->slice_num, h->slices_per_group);
@@ -285,14 +333,8 @@ static int dispatch_slice(char *buf, size_t len, struct fec_header *h,
 	ret = get_group(h, pfd, &fg);
 	if (ret < 0)
 		return ret;
-	if (group_complete(fg)) {
-		PARA_DEBUG_LOG("group complete, ignoring slice %d\n",
-			h->slice_num);
+	if (!add_slice(buf, fg))
 		return 1;
-	}
-	ret = add_slice(buf, fg);
-	if (ret < 0)
-		return ret;
 	if (group_complete(fg)) {
 		if (!pfd->fec) {
 			int k = h->data_slices_per_group, n = h->slices_per_group;
@@ -308,7 +350,7 @@ static int dispatch_slice(char *buf, size_t len, struct fec_header *h,
 	return 1;
 }
 
-static int fecdec(char *buf, size_t len, struct filter_node *fn)
+static ssize_t fecdec(char *buf, size_t len, struct filter_node *fn)
 {
 	int ret;
 	struct fec_header h;