- NUT-devel - lists.mplayerhq.hu

transport stream (for live streaming) = container + protocol IN ONE
by Jörg Hartmann 24 Sep '06

24 Sep '06

You call it "proper unix philosophy" to let the protocol handle priority and retransmission for live streaming and not to care the least for this when designing the container. But you probably know that a protocol needs to know about the content of the container (droppable frames, most important stream/channel/pictures/info parts etc.) to handle that efficiently. And that the overheads of both container and surrounding protocol add up. And you probably also know that transport streams for "live streaming" or "live broadcasting" (like MPEG-TS) are for good reasons designed as both in one: protocol and container. Or INSTEAD of both. So my question is: If you only create a container, and while doing that don't even think of how a live-streaming protocol for its use might look like, why do you think that any non-idiot would use it for live streaming at all - instead of a transport stream that is designed from the start to handle the whole of live streaming? Or if you plan to use it for live streaming: why don't you at least take the protocol part (and how both parts add up to an efficient transport system)into consideration (now and not after 1.0)? Cheers, J.H.

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spec: please rename DTS to what it actually is: DSN
by Jörg Hartmann 24 Sep '06

24 Sep '06

Hi folks, back in May 2004 Rich already found that DTS is a misnomer because it's no time stamp at all. So please call it what it is, nothing else but a decode sequence number. You probably want that people reading your spec do understand as much as possible ... Cheers, J.

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[nut]: r156 - trunk/libnut/demuxer.c
by ods15 24 Sep '06

24 Sep '06

Author: ods15 Date: Sun Sep 24 16:18:27 2006 New Revision: 156 Modified: trunk/libnut/demuxer.c Log: modify get_packet to not recurse on its own but let the caller do it. makes saw_syncpoint more accurate. Modified: trunk/libnut/demuxer.c ============================================================================== --- trunk/libnut/demuxer.c (original) +++ trunk/libnut/demuxer.c Sun Sep 24 16:18:27 2006 @@ -540,7 +540,7 @@ CHECK(get_bytes(nut->i, 1, &tmp)); } else { CHECK(get_header(nut->i, NULL)); - return get_packet(nut, pd, saw_syncpoint); + return 3; } } @@ -697,7 +697,7 @@ nut->seek_status = 0; } - err = get_packet(nut, pd, NULL); + while ((err = get_packet(nut, pd, NULL)) == 3); if (err < 0) { // some error occured! fprintf(stderr, "NUT: %s\n", nut_error(-err)); // rewind as much as possible @@ -1046,8 +1046,11 @@ if (!(nut->seek_status & 1)) while (bctello(nut->i) < end || !end) { int saw_syncpoint; nut_packet_t pd; + buf_before = bctello(nut->i); - CHECK(get_packet(nut, &pd, &saw_syncpoint)); // FIXME we're counting on syncpoint cache!! for the good_key later, and stopper_syncpoint + err = get_packet(nut, &pd, &saw_syncpoint); // FIXME we're counting on syncpoint cache!! for the good_key later, and stopper_syncpoint + if (err == 3) continue; + CHECK(err); if (saw_syncpoint) { if (stopper && !stopper_syncpoint && buf_before > stopper->pos - stopper->back_ptr + 15) { @@ -1131,7 +1134,8 @@ while (bctello(nut->i) < min_pos) { nut_packet_t pd; - CHECK(get_packet(nut, &pd, NULL)); + while ((err = get_packet(nut, &pd, NULL)) == 3); + CHECK(err); push_frame(nut, &pd); CHECK(skip_buffer(nut->i, pd.len)); }

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[nut]: r154 - trunk/libnut/demuxer.c
by ods15 24 Sep '06

24 Sep '06

Author: ods15 Date: Sun Sep 24 14:15:43 2006 New Revision: 154 Modified: trunk/libnut/demuxer.c Log: improove last commit by using first syncpoint when it is prooved to be correct. Modified: trunk/libnut/demuxer.c ============================================================================== --- trunk/libnut/demuxer.c (original) +++ trunk/libnut/demuxer.c Sun Sep 24 14:15:43 2006 @@ -339,6 +339,8 @@ if (sl->s[i].pos > sp.pos) continue; if (sp.pos < sl->s[i].pos + 16) { // syncpoint already in list sl->s[i].pos = sp.pos; + assert(!sl->s[i].pts || sl->s[i].pts == sp.pts); + sl->s[i].pts = sp.pts; if (pts) { for (j = 0; j < nut->stream_count; j++) { assert(!sl->s[i].pts_valid || sl->pts[i * nut->stream_count + j] == pts[j]); @@ -919,7 +921,8 @@ goto err_out; } if (i == 0) { // there isn't any syncpoint smaller than requested - seek_buf(nut->i, nut->last_headers, SEEK_SET); // seeking to "begginning of file", the headers + if (sl->s[0].pts) seek_buf(nut->i, sl->s[0].pos, SEEK_SET); + else seek_buf(nut->i, nut->last_headers, SEEK_SET); // seeking to "begginning of file", the headers clear_dts_cache(nut); nut->last_syncpoint = 0; goto err_out;

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[nut]: r153 - trunk/libnut/demuxer.c
by ods15 24 Sep '06

24 Sep '06

Author: ods15 Date: Sun Sep 24 14:07:19 2006 New Revision: 153 Modified: trunk/libnut/demuxer.c Log: fix long withstanding bug by seeking to headers when going past BOF instead of to syncpoint. Modified: trunk/libnut/demuxer.c ============================================================================== --- trunk/libnut/demuxer.c (original) +++ trunk/libnut/demuxer.c Sun Sep 24 14:07:19 2006 @@ -734,7 +734,7 @@ if (tmp == MAIN_STARTCODE) break; } ERROR(tmp != MAIN_STARTCODE, -ERR_NO_HEADERS); - nut->last_headers = bctello(nut->i); + nut->last_headers = bctello(nut->i) - 8; flush_buf(nut->i); } @@ -919,8 +919,7 @@ goto err_out; } if (i == 0) { // there isn't any syncpoint smaller than requested - int FIXME; // pos might not be accurate - if this function is called when there really is an index - seek_buf(nut->i, sl->s[0].pos, SEEK_SET); // seeking to first syncpoint + seek_buf(nut->i, nut->last_headers, SEEK_SET); // seeking to "begginning of file", the headers clear_dts_cache(nut); nut->last_syncpoint = 0; goto err_out;

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[nut]: r152 - trunk/libnut
by ods15 23 Sep '06

23 Sep '06

Author: ods15 Date: Sat Sep 23 22:57:50 2006 New Revision: 152 Modified: trunk/libnut/ (props changed) Log: ignore libnut.a

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[nut]: r151 - trunk/nututils/nutmerge.c
by ods15 23 Sep '06

23 Sep '06

Author: ods15 Date: Sat Sep 23 22:50:42 2006 New Revision: 151 Modified: trunk/nututils/nutmerge.c Log: update to new libnut API Modified: trunk/nututils/nutmerge.c ============================================================================== --- trunk/nututils/nutmerge.c (original) +++ trunk/nututils/nutmerge.c Sat Sep 23 22:50:42 2006 @@ -129,6 +129,7 @@ mopts.write_index = 1; mopts.fti = ft_default; mopts.max_distance = 32768; + mopts.alloc.malloc = NULL; nut = nut_muxer_init(&mopts, nut_stream, NULL); if (stats) fprintf(stats, "%10s%10s%10s%10s\n", "stream", "len", "pts_diff", "flags");

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[nut]: r150 - trunk/libnut/demuxer.c
by ods15 23 Sep '06

23 Sep '06

Author: ods15 Date: Sat Sep 23 22:50:30 2006 New Revision: 150 Modified: trunk/libnut/demuxer.c Log: bug fix, forgot to update the return Modified: trunk/libnut/demuxer.c ============================================================================== --- trunk/libnut/demuxer.c (original) +++ trunk/libnut/demuxer.c Sat Sep 23 22:50:30 2006 @@ -348,7 +348,8 @@ } sl->s[i].pts_valid = 1; } - return i; + if (out) *out = i; + return 0; } break; }

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[nut]: r149 - trunk/libnut/demuxer.c
by ods15 23 Sep '06

23 Sep '06

Author: ods15 Date: Sat Sep 23 22:18:07 2006 New Revision: 149 Modified: trunk/libnut/demuxer.c Log: the last of the malloc checks Modified: trunk/libnut/demuxer.c ============================================================================== --- trunk/libnut/demuxer.c (original) +++ trunk/libnut/demuxer.c Sat Sep 23 22:18:07 2006 @@ -740,7 +740,9 @@ CHECK(get_main_header(nut)); if (!nut->sc) { + ERROR(SIZE_MAX/sizeof(stream_context_t) < nut->stream_count+1, -ERR_OUT_OF_MEM); nut->sc = nut->alloc->malloc(sizeof(stream_context_t) * nut->stream_count); + ERROR(!nut->sc, -ERR_OUT_OF_MEM); for (i = 0; i < nut->stream_count; i++) { nut->sc[i].last_pts = 0; nut->sc[i].last_dts = 0; @@ -764,7 +766,9 @@ } CHECK(get_stream_header(nut, i)); if (!nut->sc[i].pts_cache) { + ERROR(SIZE_MAX/sizeof(int64_t) < nut->sc[i].sh.decode_delay, -ERR_OUT_OF_MEM); nut->sc[i].pts_cache = nut->alloc->malloc(nut->sc[i].sh.decode_delay * sizeof(int64_t)); + ERROR(!nut->sc[i].pts_cache, -ERR_OUT_OF_MEM); for (j = 0; j < nut->sc[i].sh.decode_delay; j++) nut->sc[i].pts_cache[j] = -1; } @@ -807,6 +811,7 @@ nut->before_seek = 0; } *s = nut->alloc->malloc(sizeof(nut_stream_header_t) * (nut->stream_count + 1)); + ERROR(!*s, -ERR_OUT_OF_MEM); for (i = 0; i < nut->stream_count; i++) (*s)[i] = nut->sc[i].sh; (*s)[i].type = -1; err_out: @@ -1252,6 +1257,7 @@ nut->seek_state = NULL; } else { if (!nut->seek_state) nut->seek_state = nut->alloc->malloc(sizeof state); + if (!nut->seek_state) return -ERR_OUT_OF_MEM; memcpy(nut->seek_state, state, sizeof state); } return err;

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[nut]: r148 - trunk/libnut/demuxer.c
by ods15 23 Sep '06

23 Sep '06

Author: ods15 Date: Sat Sep 23 22:02:03 2006 New Revision: 148 Modified: trunk/libnut/demuxer.c Log: some more malloc checks Modified: trunk/libnut/demuxer.c ============================================================================== --- trunk/libnut/demuxer.c (original) +++ trunk/libnut/demuxer.c Sat Sep 23 22:02:03 2006 @@ -84,6 +84,7 @@ } static input_buffer_t * new_mem_buffer(input_buffer_t * bc) { + if (!bc) return NULL; bc->read_len = 0; bc->write_len = 0; bc->is_mem = 1; @@ -96,6 +97,7 @@ static input_buffer_t * new_input_buffer(nut_alloc_t * alloc, nut_input_stream_t isc) { input_buffer_t * bc = new_mem_buffer(alloc->malloc(sizeof(input_buffer_t))); + if (!bc) return NULL; bc->alloc = alloc; bc->is_mem = 0; bc->isc = isc; @@ -1261,6 +1263,8 @@ if (dopts->alloc.malloc) nut = dopts->alloc.malloc(sizeof(nut_context_t)); else nut = malloc(sizeof(nut_context_t)); + if (!nut) return NULL; + nut->syncpoints.len = 0; nut->syncpoints.alloc_len = 0; nut->syncpoints.s = NULL; @@ -1287,6 +1291,11 @@ nut->i = new_input_buffer(nut->alloc, dopts->input); + if (!nut->i) { + nut->alloc->free(nut); + return NULL; + } + return nut; }

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