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[nut]: r271 - in trunk/libnut: demuxer.c priv.h
by ods15 23 Dec '06

23 Dec '06

Author: ods15 Date: Sat Dec 23 11:36:52 2006 New Revision: 271 Modified: trunk/libnut/demuxer.c trunk/libnut/priv.h Log: queue syncpoints to a linked list to avoid CPU cache trashing during playback Modified: trunk/libnut/demuxer.c ============================================================================== --- trunk/libnut/demuxer.c (original) +++ trunk/libnut/demuxer.c Sat Dec 23 11:36:52 2006 @@ -409,6 +409,30 @@ return err; } +static void add_existing_syncpoint(nut_context_t * nut, syncpoint_t sp, uint64_t * pts, uint64_t * eor, int i) { + syncpoint_list_t * sl = &nut->syncpoints; + int j; + int pts_cache = nut->dopts.cache_syncpoints & 1; + + assert(sl->s[i].pos <= sp.pos && sp.pos < sl->s[i].pos + 16); // code sanity + + assert(!sl->s[i].pts || sl->s[i].pts == sp.pts); + assert(!sl->s[i].back_ptr || sl->s[i].back_ptr == sp.back_ptr); + sl->s[i].pos = sp.pos; + sl->s[i].pts = sp.pts; + sl->s[i].back_ptr = sp.back_ptr; + if (pts_cache && sp.pts_valid) { + for (j = 0; j < nut->stream_count; j++) { + assert(!sl->s[i].pts_valid || sl->pts[i * nut->stream_count + j] == pts[j]); + assert(!sl->s[i].pts_valid || sl->eor[i * nut->stream_count + j] == eor[j]); + sl->pts[i * nut->stream_count + j] = pts[j]; + sl->eor[i * nut->stream_count + j] = eor[j]; + } + sl->s[i].pts_valid = 1; + } + if (sp.pts_valid && i) sl->s[i-1].seen_next = 1; +} + static int add_syncpoint(nut_context_t * nut, syncpoint_t sp, uint64_t * pts, uint64_t * eor, int * out) { syncpoint_list_t * sl = &nut->syncpoints; int i, j, err = 0; @@ -419,21 +443,7 @@ for (i = sl->len; i--; ) { // more often than not, we're adding at end of list if (sl->s[i].pos > sp.pos) continue; if (sp.pos < sl->s[i].pos + 16) { // syncpoint already in list - assert(!sl->s[i].pts || sl->s[i].pts == sp.pts); - assert(!sl->s[i].back_ptr || sl->s[i].back_ptr == sp.back_ptr); - sl->s[i].pos = sp.pos; - sl->s[i].pts = sp.pts; - sl->s[i].back_ptr = sp.back_ptr; - if (pts_cache && sp.pts_valid) { - for (j = 0; j < nut->stream_count; j++) { - assert(!sl->s[i].pts_valid || sl->pts[i * nut->stream_count + j] == pts[j]); - assert(!sl->s[i].pts_valid || sl->eor[i * nut->stream_count + j] == eor[j]); - sl->pts[i * nut->stream_count + j] = pts[j]; - sl->eor[i * nut->stream_count + j] = eor[j]; - } - sl->s[i].pts_valid = 1; - } - if (sp.pts_valid && i) sl->s[i-1].seen_next = 1; + add_existing_syncpoint(nut, sp, pts, eor, i); if (out) *out = i; return 0; } @@ -470,6 +480,62 @@ return err; } +static int queue_add_syncpoint(nut_context_t * nut, syncpoint_t sp, uint64_t * pts, uint64_t * eor) { + syncpoint_list_t * sl = &nut->syncpoints; + syncpoint_linked_t * s; + size_t malloc_size; + int pts_cache = nut->dopts.cache_syncpoints & 1; + int err = 0; + int i = sl->cached_pos; + + if (i >= sl->len) i = sl->len - 1; + + while (sl->s[i].pos > sp.pos && i) i--; + while (sl->s[i+1].pos <= sp.pos && i < sl->len-1) i++; + // Result: sl->s[i].pos <= sp.pos < sl->s[i+1].pos + sl->cached_pos = i; + + if (sl->s[i].pos <= sp.pos && sp.pos < sl->s[i].pos + 16) { // syncpoint already in list + add_existing_syncpoint(nut, sp, pts, eor, i); + return 0; + } + + malloc_size = sizeof(syncpoint_linked_t) - sizeof(uint64_t); + if (pts_cache && sp.pts_valid) { + assert(pts && eor); // code sanity check + malloc_size += (nut->stream_count*2) * sizeof(uint64_t); + } + + SAFE_CALLOC(nut->alloc, s, 1, malloc_size); + + s->s = sp; + if (pts_cache && sp.pts_valid) { + for (i = 0; i < nut->stream_count; i++) { + s->pts_eor[i] = pts[i]; + s->pts_eor[i+nut->stream_count] = eor[i]; + } + } + + s->prev = sl->linked; + sl->linked = s; +err_out: + return err; +} + +static int flush_syncpoint_queue(nut_context_t * nut) { + syncpoint_list_t * sl = &nut->syncpoints; + int err = 0; + while (sl->linked) { + syncpoint_linked_t * s = sl->linked; + CHECK(add_syncpoint(nut, s->s, s->pts_eor, s->pts_eor + nut->stream_count, NULL)); + sl->linked = s->prev; + nut->alloc->free(s); + } +err_out: + return err; +} + + static void set_global_pts(nut_context_t * nut, uint64_t pts) { int i; TO_PTS(timestamp, pts) @@ -510,7 +576,10 @@ nut->sc[i].last_key = 0; nut->sc[i].eor = 0; } - CHECK(add_syncpoint(nut, s, pts, eor, NULL)); + if (nut->dopts.cache_syncpoints & 2) // during seeking, syncpoints go into cache immediately + CHECK(add_syncpoint(nut, s, pts, eor, NULL)); + else // otherwise, queue to a linked list to avoid CPU cache trashing during playback + CHECK(queue_add_syncpoint(nut, s, pts, eor)); } err_out: return err; @@ -844,6 +913,8 @@ ERROR(!(nut->dopts.cache_syncpoints & 1) || !sl->len, -1); + flush_syncpoint_queue(nut); + if (i) i--; else { for (i = 0; i < sl->len; i++) if (sl->s[i].pos+15 > pos) break; @@ -1351,6 +1422,7 @@ for (i = 0; i < nut->stream_count; i++) nut->sc[i].state.pts = (uint64_t)(time_pos / TO_TB(i).nom * TO_TB(i).den); nut->seek_time_pos = time_pos; nut->dopts.cache_syncpoints |= 2; + flush_syncpoint_queue(nut); } else { time_pos = nut->seek_time_pos; } @@ -1436,6 +1508,8 @@ nut->syncpoints.s = NULL; nut->syncpoints.pts = NULL; nut->syncpoints.eor = NULL; + nut->syncpoints.cached_pos = 0; + nut->syncpoints.linked = NULL; nut->sc = NULL; nut->tb = NULL; @@ -1490,6 +1564,11 @@ nut->alloc->free(nut->syncpoints.s); nut->alloc->free(nut->syncpoints.pts); nut->alloc->free(nut->syncpoints.eor); + while (nut->syncpoints.linked) { + syncpoint_linked_t * s = nut->syncpoints.linked; + nut->syncpoints.linked = s->prev; + nut->alloc->free(s); + } nut->alloc->free(nut->sc); nut->alloc->free(nut->tmp_buffer); // the caller's allocated stream list nut->alloc->free(nut->info); Modified: trunk/libnut/priv.h ============================================================================== --- trunk/libnut/priv.h (original) +++ trunk/libnut/priv.h Sat Dec 23 11:36:52 2006 @@ -75,12 +75,21 @@ unsigned int pts_valid:1; } syncpoint_t; +typedef struct syncpoint_linked_s syncpoint_linked_t; +struct syncpoint_linked_s { + syncpoint_linked_t * prev; + syncpoint_t s; + uint64_t pts_eor[1]; +}; + typedef struct { int len; int alloc_len; syncpoint_t * s; uint64_t * pts; // each elem is stream_count items, +1 to real pts, 0 means there is no key uint64_t * eor; // same as pts, is the pts of last eor in syncpoint region _IF_ eor is set by syncpoint. + int cached_pos; + syncpoint_linked_t * linked; // entires are entered in reverse order for speed, points to END of list } syncpoint_list_t; typedef struct {

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[nut]: r270 - trunk/libnut/demuxer.c
by ods15 23 Dec '06

23 Dec '06

Author: ods15 Date: Sat Dec 23 10:33:36 2006 New Revision: 270 Modified: trunk/libnut/demuxer.c Log: some cosmetics and code-reorginazation/readability Modified: trunk/libnut/demuxer.c ============================================================================== --- trunk/libnut/demuxer.c (original) +++ trunk/libnut/demuxer.c Sat Dec 23 10:33:36 2006 @@ -412,23 +412,23 @@ static int add_syncpoint(nut_context_t * nut, syncpoint_t sp, uint64_t * pts, uint64_t * eor, int * out) { syncpoint_list_t * sl = &nut->syncpoints; int i, j, err = 0; + int pts_cache = nut->dopts.cache_syncpoints & 1; - assert(nut->dopts.cache_syncpoints & 1 || !pts); // pts information is never stored with no syncpoint cache - if (nut->dopts.cache_syncpoints & 1 && sp.pts_valid) assert(pts && eor); // code sanity check + if (pts_cache && sp.pts_valid) assert(pts && eor); // code sanity check for (i = sl->len; i--; ) { // more often than not, we're adding at end of list 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; assert(!sl->s[i].back_ptr || sl->s[i].back_ptr == sp.back_ptr); + sl->s[i].pos = sp.pos; + sl->s[i].pts = sp.pts; sl->s[i].back_ptr = sp.back_ptr; - if (nut->dopts.cache_syncpoints & 1 && sp.pts_valid) { + if (pts_cache && sp.pts_valid) { for (j = 0; j < nut->stream_count; j++) { assert(!sl->s[i].pts_valid || sl->pts[i * nut->stream_count + j] == pts[j]); - sl->pts[i * nut->stream_count + j] = pts[j]; assert(!sl->s[i].pts_valid || sl->eor[i * nut->stream_count + j] == eor[j]); + sl->pts[i * nut->stream_count + j] = pts[j]; sl->eor[i * nut->stream_count + j] = eor[j]; } sl->s[i].pts_valid = 1; @@ -443,7 +443,7 @@ if (sl->len + 1 > sl->alloc_len) { sl->alloc_len += PREALLOC_SIZE/4; SAFE_REALLOC(nut->alloc, sl->s, sizeof(syncpoint_t), sl->alloc_len); - if (nut->dopts.cache_syncpoints & 1) { + if (pts_cache) { SAFE_REALLOC(nut->alloc, sl->pts, nut->stream_count * sizeof(uint64_t), sl->alloc_len); SAFE_REALLOC(nut->alloc, sl->eor, nut->stream_count * sizeof(uint64_t), sl->alloc_len); } @@ -451,11 +451,11 @@ memmove(sl->s + i + 1, sl->s + i, (sl->len - i) * sizeof(syncpoint_t)); sl->s[i] = sp; if (sl->s[i].pts_valid) { - if (!(nut->dopts.cache_syncpoints & 1)) sl->s[i].pts_valid = 0; // pts_valid is not really true, only used for seen_next + if (!pts_cache) sl->s[i].pts_valid = 0; // pts_valid is not really true, only used for seen_next if (i) sl->s[i-1].seen_next = 1; } - if (nut->dopts.cache_syncpoints & 1) { + if (pts_cache) { memmove(sl->pts + (i + 1) * nut->stream_count, sl->pts + i * nut->stream_count, (sl->len - i) * nut->stream_count * sizeof(uint64_t)); memmove(sl->eor + (i + 1) * nut->stream_count, sl->eor + i * nut->stream_count, (sl->len - i) * nut->stream_count * sizeof(uint64_t)); for (j = 0; j < nut->stream_count; j++) { @@ -500,19 +500,17 @@ s.seen_next = 0; s.pts_valid = !after_seek; - if (nut->dopts.cache_syncpoints & 1) { + if (nut->dopts.cache_syncpoints) { // either we're using syncpoint cache, or we're seeking and we need the cache int i; uint64_t pts[nut->stream_count]; uint64_t eor[nut->stream_count]; for (i = 0; i < nut->stream_count; i++) { pts[i] = nut->sc[i].last_key; - nut->sc[i].last_key = 0; eor[i] = nut->sc[i].eor; + nut->sc[i].last_key = 0; nut->sc[i].eor = 0; } CHECK(add_syncpoint(nut, s, pts, eor, NULL)); - } else if (nut->dopts.cache_syncpoints) { // we're seeking, we need syncpoint cache - CHECK(add_syncpoint(nut, s, NULL, NULL, NULL)); } err_out: return err;

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[nut]: r269 - trunk/libnut/demuxer.c
by ods15 23 Dec '06

23 Dec '06

Author: ods15 Date: Sat Dec 23 10:02:48 2006 New Revision: 269 Modified: trunk/libnut/demuxer.c Log: make add_syncpoint() handle seen_next via pts_valid flag. Modified: trunk/libnut/demuxer.c ============================================================================== --- trunk/libnut/demuxer.c (original) +++ trunk/libnut/demuxer.c Sat Dec 23 10:02:48 2006 @@ -414,6 +414,8 @@ int i, j, err = 0; assert(nut->dopts.cache_syncpoints & 1 || !pts); // pts information is never stored with no syncpoint cache + if (nut->dopts.cache_syncpoints & 1 && sp.pts_valid) assert(pts && eor); // code sanity check + for (i = sl->len; i--; ) { // more often than not, we're adding at end of list if (sl->s[i].pos > sp.pos) continue; if (sp.pos < sl->s[i].pos + 16) { // syncpoint already in list @@ -422,7 +424,7 @@ sl->s[i].pts = sp.pts; assert(!sl->s[i].back_ptr || sl->s[i].back_ptr == sp.back_ptr); sl->s[i].back_ptr = sp.back_ptr; - if (pts) { + if (nut->dopts.cache_syncpoints & 1 && sp.pts_valid) { for (j = 0; j < nut->stream_count; j++) { assert(!sl->s[i].pts_valid || sl->pts[i * nut->stream_count + j] == pts[j]); sl->pts[i * nut->stream_count + j] = pts[j]; @@ -431,6 +433,7 @@ } sl->s[i].pts_valid = 1; } + if (sp.pts_valid && i) sl->s[i-1].seen_next = 1; if (out) *out = i; return 0; } @@ -447,14 +450,17 @@ } memmove(sl->s + i + 1, sl->s + i, (sl->len - i) * sizeof(syncpoint_t)); sl->s[i] = sp; - assert(sl->s[i].pts_valid == !!pts); + if (sl->s[i].pts_valid) { + if (!(nut->dopts.cache_syncpoints & 1)) sl->s[i].pts_valid = 0; // pts_valid is not really true, only used for seen_next + if (i) sl->s[i-1].seen_next = 1; + } if (nut->dopts.cache_syncpoints & 1) { memmove(sl->pts + (i + 1) * nut->stream_count, sl->pts + i * nut->stream_count, (sl->len - i) * nut->stream_count * sizeof(uint64_t)); memmove(sl->eor + (i + 1) * nut->stream_count, sl->eor + i * nut->stream_count, (sl->len - i) * nut->stream_count * sizeof(uint64_t)); for (j = 0; j < nut->stream_count; j++) { - sl->pts[i * nut->stream_count + j] = pts ? pts[j] : 0; - sl->eor[i * nut->stream_count + j] = eor ? eor[j] : 0; + sl->pts[i * nut->stream_count + j] = sl->s[i].pts_valid ? pts[j] : 0; + sl->eor[i * nut->stream_count + j] = sl->s[i].pts_valid ? eor[j] : 0; } } @@ -493,7 +499,7 @@ set_global_pts(nut, s.pts); s.seen_next = 0; - s.pts_valid = 0; + s.pts_valid = !after_seek; if (nut->dopts.cache_syncpoints & 1) { int i; uint64_t pts[nut->stream_count]; @@ -504,16 +510,9 @@ eor[i] = nut->sc[i].eor; nut->sc[i].eor = 0; } - if (after_seek) CHECK(add_syncpoint(nut, s, NULL, NULL, NULL)); - else { - s.pts_valid = 1; - CHECK(add_syncpoint(nut, s, pts, eor, &i)); - nut->syncpoints.s[i - 1].seen_next = 1; - } + CHECK(add_syncpoint(nut, s, pts, eor, NULL)); } else if (nut->dopts.cache_syncpoints) { // we're seeking, we need syncpoint cache - int i; - CHECK(add_syncpoint(nut, s, NULL, NULL, &i)); - if (!after_seek) nut->syncpoints.s[i - 1].seen_next = 1; + CHECK(add_syncpoint(nut, s, NULL, NULL, NULL)); } err_out: return err;

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[nut]: r268 - trunk/libnut/libnut.h
by ods15 22 Dec '06

22 Dec '06

Author: ods15 Date: Fri Dec 22 11:26:03 2006 New Revision: 268 Modified: trunk/libnut/libnut.h Log: typo fix Modified: trunk/libnut/libnut.h ============================================================================== --- trunk/libnut/libnut.h (original) +++ trunk/libnut/libnut.h Fri Dec 22 11:26:03 2006 @@ -54,7 +54,7 @@ uint64_t max_pts; ///< Only used in demuxer. If non-zero, then it is the highest value in stream /// \name Video - /// Only used is type is #NUT_VIDEO_CLASS @{ + /// Only used if type is #NUT_VIDEO_CLASS @{ int width; ///< Width of video in pixels int height; ///< Height of video in pixels int sample_width; ///< Ratio to stretch the video. May only be zero if #sample_height is zero @@ -62,7 +62,7 @@ int colorspace_type; /// \name audio - /// Only used is type is #NUT_AUDIO_CLASS @{ + /// Only used if type is #NUT_AUDIO_CLASS @{ int samplerate_nom; ///< Sample rate of audio. Example: 44100 int samplerate_denom; ///< Sample rate denominator of audio. Example: 1 int channel_count; ///< Amount of audio channels

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[nut]: r267 - trunk/libnut/libnut.h
by ods15 22 Dec '06

22 Dec '06

Author: ods15 Date: Fri Dec 22 11:25:04 2006 New Revision: 267 Modified: trunk/libnut/libnut.h Log: small doxygen simplify Modified: trunk/libnut/libnut.h ============================================================================== --- trunk/libnut/libnut.h (original) +++ trunk/libnut/libnut.h Fri Dec 22 11:25:04 2006 @@ -61,14 +61,11 @@ int sample_height; ///< Ratio to stretch the video. May only be zero if #sample_width is zero int colorspace_type; - /// @} /// \name audio /// Only used is type is #NUT_AUDIO_CLASS @{ int samplerate_nom; ///< Sample rate of audio. Example: 44100 int samplerate_denom; ///< Sample rate denominator of audio. Example: 1 int channel_count; ///< Amount of audio channels - - /// @} } nut_stream_header_t; /// Single info field struct \ingroup demuxer muxer

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r21405 - trunk/DOCS/tech/nut.txt
by ivo 30 Nov '06

30 Nov '06

Author: ivo Date: Thu Nov 30 22:59:55 2006 New Revision: 21405 Modified: trunk/DOCS/tech/nut.txt Log: move reserved_bytes out of packet_footer. this makes all packets uniform. Modified: trunk/DOCS/tech/nut.txt ============================================================================== --- trunk/DOCS/tech/nut.txt (original) +++ trunk/DOCS/tech/nut.txt Thu Nov 30 22:59:55 2006 @@ -215,9 +215,7 @@ header_checksum u(32) packet_footer - reserved_bytes checksum u(32) - [Note: in index packet, reserved_bytes comes before index_ptr] reserved_headers while(next_byte == 'N' && next_code != main_startcode @@ -226,6 +224,7 @@ && next_code != index_startcode && next_code != syncpoint_startcode){ packet_header + reserved_bytes packet_footer } @@ -272,6 +271,7 @@ reserved_count[i]= tmp_res; } } + reserved_bytes stream_header: stream_id v @@ -294,6 +294,7 @@ samplerate_denom v channel_count v } + reserved_bytes Basic Packets: @@ -394,10 +395,12 @@ type= "v" } } + reserved_bytes syncpoint: global_key_pts t back_ptr_div16 v + reserved_bytes Complete definition:

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reserved bytes
by Ivo 28 Nov '06

28 Nov '06

Hi, I stumbled upon the following: packet_footer reserved_bytes checksum u(32) [Note: in index packet, reserved_bytes comes before index_ptr] Wouldn't it be cleaner and easier to understand to just move reserved_bytes to the end of each header? Like: packet_header .... some_header (!=index) .... reserved_bytes packet_footer checksum u(32) and packet_header .... index .... reserved_bytes index_ptr f(64) packet_footer checksum u(32) This removes the need for the [Note:...]-exception for index packets and should result in the same bitstream as before. --Ivo

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a few things about nut.txt
by Ivo 27 Nov '06

27 Nov '06

Hi, While reading the spec, I noticed a few things that could improve readability IMHO: 1.) It would be handy to have the type mentioned after each tag in the tag description section. It is tiresome to have to scroll back each time. e.g. chapter_id (s) stream_class (v) fourcc (vb) et cetera 2.) The first column of the frame_flags table is called Bit, but there is no such thing as the 4096th bit of a 64-bit value. I suggest changing the column-heading to Mask or change the column-entries to represent the bit number (i.e. 0, 1, 3, 4, 5, 6, 7, 12, 13). 3.) There is no explanation of what EOR actually means. I could change 1.) and 2.) if nobody objects. For 3.) I need an explanation first :-) --Ivo

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r21294 - trunk/DOCS/tech/nut.txt
by ivo 26 Nov '06

26 Nov '06

Author: ivo Date: Sun Nov 26 23:50:47 2006 New Revision: 21294 Modified: trunk/DOCS/tech/nut.txt Log: rename all *_nom (nominator) to the correct *_num (numerator) Modified: trunk/DOCS/tech/nut.txt ============================================================================== --- trunk/DOCS/tech/nut.txt (original) +++ trunk/DOCS/tech/nut.txt Sun Nov 26 23:50:47 2006 @@ -237,9 +237,9 @@ max_distance v time_base_count v for(i=0; i<time_base_count; i++) - time_base_nom v + time_base_num v time_base_denom v - time_base[i]= time_base_nom/time_base_denom + time_base[i]= time_base_num/time_base_denom tmp_pts=0 tmp_mul=1 tmp_stream=0 @@ -290,7 +290,7 @@ sample_height v colorspace_type v }else if(stream_class == audio){ - samplerate_nom v + samplerate_num v samplerate_denom v channel_count v } @@ -495,14 +495,14 @@ the id values used are the same as in avi, so if a codec uses a specific fourcc in avi then the same fourcc MUST be used here -time_base_nom (v) / time_base_denom (v) = time_base +time_base_num (v) / time_base_denom (v) = time_base the length of a timer tick in seconds, this MUST be equal to the 1/fps if FLAG_FIXED_FPS is set - time_base_nom and time_base_denom MUST NOT be 0 - time_base_nom and time_base_denom MUST be relatively prime + time_base_num and time_base_denom MUST NOT be 0 + time_base_num and time_base_denom MUST be relatively prime time_base_denom MUST be < 2^31 examples: - fps time_base_nom time_base_denom + fps time_base_num time_base_denom 30 1 30 29.97 1001 30000 23.976 1001 24000 @@ -517,10 +517,10 @@ To switch from 2 different timebases, the following calculation is defined: - ln = from_time_base_nom*to_time_base_denom + ln = from_time_base_num*to_time_base_denom sn = from_timestamp d1 = from_time_base_denom - d2 = to_time_base_nom + d2 = to_time_base_num timestamp = (ln/d1*sn + ln%d1*sn/d1)/d2 Note: this calculation MUST be done with unsigned 64 bit integers, and is equivalent to (ln*sn)/(d1*d2) but this would require a 96bit integer @@ -711,7 +711,7 @@ 17 ITU Rec 624 / ITU Rec 601 Y range: 0..255 Cb/Cr range: 0..255 18 ITU Rec 709 Y range: 0..255 Cb/Cr range: 0..255 -samplerate_nom (v) / samplerate_denom (v) = samplerate +samplerate_num (v) / samplerate_denom (v) = samplerate the number of samples per second, MUST NOT be 0 crc32 checksum

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typo?
by Ivo 26 Nov '06

26 Nov '06

Hi, In the description of an info packet, I found the following: .... }else if (value<-4){ type= "r" value.den= -value-4 value.num s }else{ .... I suppose that should be "value.nom" ? --Ivo

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