/*************************************************************************** * __________ __ ___. * Open \______ \ ____ ____ | | _\_ |__ _______ ___ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ * \/ \/ \/ \/ \/ * * Parser for MPEG streams * * Copyright (c) 2007 Michael Sevakis * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * ****************************************************************************/ #include "plugin.h" #include "mpegplayer.h" struct stream_parser str_parser SHAREDBSS_ATTR; static void parser_init_state(void) { str_parser.last_seek_time = 0; str_parser.format = STREAM_FMT_UNKNOWN; str_parser.start_pts = INVALID_TIMESTAMP; str_parser.end_pts = INVALID_TIMESTAMP; str_parser.flags = 0; str_parser.dims.w = 0; str_parser.dims.h = 0; } /* Place the stream in a state to begin parsing - sync will be performed * first */ void str_initialize(struct stream *str, off_t pos) { /* Initial positions start here */ str->hdr.win_left = str->hdr.win_right = pos; /* No packet */ str->curr_packet = NULL; /* Pick up parsing from this point in the buffer */ str->curr_packet_end = disk_buf_offset2ptr(pos); /* No flags */ str->pkt_flags = 0; /* Sync first */ str->state = SSTATE_SYNC; } /* Place the stream in an end of data state */ void str_end_of_stream(struct stream *str) { /* Offsets that prevent this stream from being included in the * min left/max right window so that no buffering is triggered on * its behalf. Set right to the min first so a thread reading the * overall window gets doesn't see this as valid no matter what the * file length. */ str->hdr.win_right = OFF_T_MIN; str->hdr.win_left = OFF_T_MAX; /* No packets */ str->curr_packet = str->curr_packet_end = NULL; /* No flags */ str->pkt_flags = 0; /* Fin */ str->state = SSTATE_END; } /* Return a timestamp at address p+offset if the marker bits are in tact */ static inline uint32_t read_pts(uint8_t *p, off_t offset) { return TS_CHECK_MARKERS(p, offset) ? TS_FROM_HEADER(p, offset) : INVALID_TIMESTAMP; } static inline bool validate_timestamp(uint32_t ts) { return ts >= str_parser.start_pts && ts <= str_parser.end_pts; } /* Find a start code before or after a given position */ uint8_t * mpeg_parser_scan_start_code(struct stream_scan *sk, uint32_t code) { stream_scan_normalize(sk); if (sk->dir < 0) { /* Reverse scan - start with at least the min needed */ stream_scan_offset(sk, 4); } code &= 0xff; /* Only the low byte matters */ while (sk->len >= 0 && sk->margin >= 4) { uint8_t *p; off_t pos = disk_buf_lseek(sk->pos, SEEK_SET); ssize_t len = disk_buf_getbuffer_l2(&sk->l2, 4, &p); if (pos < 0 || len < 4) break; if (CMP_3_CONST(p, PACKET_START_CODE_PREFIX) && p[3] == code) { return p; } stream_scan_offset(sk, 1); } return NULL; } /* Find a PES packet header for any stream - return stream to which it * belongs */ unsigned mpeg_parser_scan_pes(struct stream_scan *sk) { stream_scan_normalize(sk); if (sk->dir < 0) { /* Reverse scan - start with at least the min needed */ stream_scan_offset(sk, 4); } while (sk->len >= 0 && sk->margin >= 4) { uint8_t *p; off_t pos = disk_buf_lseek(sk->pos, SEEK_SET); ssize_t len = disk_buf_getbuffer_l2(&sk->l2, 4, &p); if (pos < 0 || len < 4) break; if (CMP_3_CONST(p, PACKET_START_CODE_PREFIX)) { unsigned id = p[3]; if (id >= 0xb9) return id; /* PES header */ /* else some video stream element */ } stream_scan_offset(sk, 1); } return -1; } /* Return the first SCR found from the scan direction */ uint32_t mpeg_parser_scan_scr(struct stream_scan *sk) { uint8_t *p = mpeg_parser_scan_start_code(sk, MPEG_STREAM_PACK_HEADER); if (p != NULL && sk->margin >= 9) /* 9 bytes total required */ { sk->data = 9; if ((p[4] & 0xc0) == 0x40) /* mpeg-2 */ { /* Lookhead p+8 */ if (MPEG2_CHECK_PACK_SCR_MARKERS(p, 4)) return MPEG2_PACK_HEADER_SCR(p, 4); } else if ((p[4] & 0xf0) == 0x20) /* mpeg-1 */ { /* Lookahead p+8 */ if (TS_CHECK_MARKERS(p, 4)) return TS_FROM_HEADER(p, 4); } /* Weird pack header */ sk->data = 5; } return INVALID_TIMESTAMP; } uint32_t mpeg_parser_scan_pts(struct stream_scan *sk, unsigned id) { stream_scan_normalize(sk); if (sk->dir < 0) { /* Reverse scan - start with at least the min needed */ stream_scan_offset(sk, 4); } while (sk->len >= 0 && sk->margin >= 4) { uint8_t *p; off_t pos = disk_buf_lseek(sk->pos, SEEK_SET); ssize_t len = disk_buf_getbuffer_l2(&sk->l2, 30, &p); if (pos < 0 || len < 4) break; if (CMP_3_CONST(p, PACKET_START_CODE_PREFIX) && p[3] == id) { uint8_t *h = p; if (sk->margin < 7) { /* Insufficient data */ } else if ((h[6] & 0xc0) == 0x80) /* mpeg2 */ { if (sk->margin >= 14 && (h[7] & 0x80) != 0x00) { sk->data = 14; return read_pts(h, 9); } } else /* mpeg1 */ { ssize_t l = 6; ssize_t margin = sk->margin; /* Skip stuffing_byte */ while (margin > 7 && h[l] == 0xff && ++l <= 22) --margin; if (margin >= 7) { if ((h[l] & 0xc0) == 0x40) { /* Skip STD_buffer_scale and STD_buffer_size */ margin -= 2; l += 2; } if (margin >= 5) { /* Header points to the mpeg1 pes header */ h += l; if ((h[0] & 0xe0) == 0x20) { /* PTS or PTS_DTS indicated */ sk->data = (h + 5) - p; return read_pts(h, 0); } } } } /* No PTS present - keep searching for a matching PES header with * one */ } stream_scan_offset(sk, 1); } return INVALID_TIMESTAMP; } static bool init_video_info(void) { DEBUGF("Getting movie size\n"); /* The decoder handles this in order to initialize its knowledge of the * movie parameters making seeking easier */ str_send_msg(&video_str, STREAM_RESET, 0); if (str_send_msg(&video_str, VIDEO_GET_SIZE, (intptr_t)&str_parser.dims) != 0) { return true; } DEBUGF(" failed\n"); return false; } static bool init_times(struct stream *str) { struct stream tmp_str; const ssize_t filesize = disk_buf_filesize(); const ssize_t max_probe = MIN(512*1024, filesize); bool found_stream; /* Simply find the first earliest timestamp - this will be the one * used when streaming anyway */ DEBUGF("Finding start_pts: 0x%02x\n", str->id); found_stream = false; str->start_pts = INVALID_TIMESTAMP; str->end_pts = INVALID_TIMESTAMP; tmp_str.id = str->id; tmp_str.hdr.pos = 0; tmp_str.hdr.limit = max_probe; /* Probe for many for the start because some stamps could be anomalous. * Video also can also have things out of order. Just see what it's got. */ while (1) { switch (parser_get_next_data(&tmp_str, STREAM_PM_RANDOM_ACCESS)) { case STREAM_DATA_END: break; case STREAM_OK: found_stream = true; if (tmp_str.pkt_flags & PKT_HAS_TS) { if (tmp_str.pts < str->start_pts) str->start_pts = tmp_str.pts; } continue; } break; } if (!found_stream) { DEBUGF(" stream not found:0x%02x\n", str->id); return false; } DEBUGF(" start:%u\n", (unsigned)str->start_pts); /* Use the decoder thread to perform a synchronized search - no * decoding should take place but just a simple run through timestamps * and durations as the decoder would see them. This should give the * precise time at the end of the last frame for the stream. */ DEBUGF("Finding end_pts: 0x%02x\n", str->id); str_parser.parms.sd.time = MAX_TIMESTAMP; str_parser.parms.sd.sk.pos = filesize - max_probe; str_parser.parms.sd.sk.len = max_probe; str_parser.parms.sd.sk.dir = SSCAN_FORWARD; str_send_msg(str, STREAM_RESET, 0); if (str_send_msg(str, STREAM_FIND_END_TIME, (intptr_t)&str_parser.parms.sd) == STREAM_PERFECT_MATCH) { str->end_pts = str_parser.parms.sd.time; DEBUGF(" end:%u\n", (unsigned)str->end_pts); } return true; } static bool check_times(const struct stream *str) { return str->start_pts < str->end_pts && str->end_pts != INVALID_TIMESTAMP; } /* Return the best-fit file offset of a timestamp in the PES where * timstamp <= time < next timestamp. Will try to return something reasonably * valid if best-fit could not be made. */ static off_t mpeg_parser_seek_PTS(uint32_t time, unsigned id) { ssize_t pos_left = 0; ssize_t pos_right = disk_buf.filesize; ssize_t pos, pos_new; uint32_t time_left = str_parser.start_pts; uint32_t time_right = str_parser.end_pts; uint32_t pts = 0; uint32_t prevpts = 0; enum state_enum state = STATE0; struct stream_scan sk; stream_scan_init(&sk); /* Initial estimate taken from average bitrate - later interpolations are * taken similarly based on the remaining file interval */ pos_new = muldiv_uint32(time - time_left, pos_right - pos_left, time_right - time_left) + pos_left; /* return this estimated position if nothing better comes up */ pos = pos_new; DEBUGF("Seeking stream 0x%02x\n", id); DEBUGF("$$ tl:%u t:%u ct:?? tr:%u\n pl:%ld pn:%ld pr:%ld\n", (unsigned)time_left, (unsigned)time, (unsigned)time_right, (long)pos_left, (long)pos_new, (long)pos_right); sk.dir = SSCAN_REVERSE; while (state < STATE9) { uint32_t currpts; sk.pos = pos_new; sk.len = (sk.dir < 0) ? pos_new - pos_left : pos_right - pos_new; currpts = mpeg_parser_scan_pts(&sk, id); if (currpts != INVALID_TIMESTAMP) { ssize_t pos_adj; /* Adjustment to over or under-estimate */ /* Found a valid timestamp - see were it lies in relation to * target */ if (currpts < time) { /* Time at current position is before seek time - move * forward */ if (currpts > pts) { /* This is less than the desired time but greater than * the currently seeked one; move the position up */ pts = currpts; pos = sk.pos; } /* No next timestamp can be sooner */ pos_left = sk.pos + sk.data; time_left = currpts; if (pos_right <= pos_left) break; /* If the window disappeared - we're done */ pos_new = muldiv_uint32(time - time_left, pos_right - pos_left, time_right - time_left); /* Point is ahead of us - fudge estimate a bit high */ pos_adj = pos_new / 10; if (pos_adj > 512*1024) pos_adj = 512*1024; pos_new += pos_left + pos_adj; if (pos_new >= pos_right) { /* Estimate could push too far */ pos_new = pos_right; } state = STATE2; /* Last scan was early */ sk.dir = SSCAN_REVERSE; DEBUGF(">> tl:%u t:%u ct:%u tr:%u\n pl:%ld pn:%ld pr:%ld\n", (unsigned)time_left, (unsigned)time, (unsigned)currpts, (unsigned)time_right, (long)pos_left, (long)pos_new, (long)pos_right); } else if (currpts > time) { /* Time at current position is past seek time - move backward */ pos_right = sk.pos; time_right = currpts; if (pos_right <= pos_left) break; /* If the window disappeared - we're done */ pos_new = muldiv_uint32(time - time_left, pos_right - pos_left, time_right - time_left); /* Overshot the seek point - fudge estimate a bit low */ pos_adj = pos_new / 10; if (pos_adj > 512*1024) pos_adj = 512*1024; pos_new += pos_left - pos_adj; state = STATE3; /* Last scan was late */ sk.dir = SSCAN_REVERSE; DEBUGF("<< tl:%u t:%u ct:%u tr:%u\n pl:%ld pn:%ld pr:%ld\n", (unsigned)time_left, (unsigned)time, (unsigned)currpts, (unsigned)time_right, (long)pos_left, (long)pos_new, (long)pos_right); } else { /* Exact match - it happens */ DEBUGF("|| tl:%u t:%u ct:%u tr:%u\n pl:%ld pn:%ld pr:%ld\n", (unsigned)time_left, (unsigned)time, (unsigned)currpts, (unsigned)time_right, (long)pos_left, (long)pos_new, (long)pos_right); pts = currpts; pos = sk.pos; state = STATE9; } } else { /* Nothing found */ switch (state) { case STATE1: /* We already tried the bruteforce scan and failed again - no * more stamps could possibly exist in the interval */ DEBUGF("!! no timestamp 2x\n"); break; case STATE0: /* Hardly likely except at very beginning - just do L->R scan * to find something */ DEBUGF("!! no timestamp on first probe: %jd\n", (intmax_t) sk.pos); case STATE2: case STATE3: /* Could just be missing timestamps because the interval is * narrowing down. A large block of data from another stream * may also be in the midst of our chosen points which could * cluster at either extreme end. If anything is there, this * will find it. */ pos_new = pos_left; sk.dir = SSCAN_FORWARD; DEBUGF("?? tl:%u t:%u ct:%u tr:%u\n pl:%ld pn:%ld pr:%ld\n", (unsigned)time_left, (unsigned)time, (unsigned)currpts, (unsigned)time_right, (long)pos_left, (long)pos_new, (long)pos_right); state = STATE1; break; default: DEBUGF("?? Invalid state: %d\n", state); } } /* Same timestamp twice = quit */ if (currpts == prevpts) { DEBUGF("!! currpts == prevpts (stop)\n"); state = STATE9; } prevpts = currpts; } #if defined(DEBUG) || defined(SIMULATOR) /* The next pts after the seeked-to position should be greater - * most of the time - frames out of presentation order may muck it * up a slight bit */ sk.pos = pos + 1; sk.len = disk_buf.filesize; sk.dir = SSCAN_FORWARD; uint32_t nextpts = mpeg_parser_scan_pts(&sk, id); DEBUGF("Seek pos:%ld pts:%u t:%u next pts:%u \n", (long)pos, (unsigned)pts, (unsigned)time, (unsigned)nextpts); if (pts <= time && time < nextpts) { /* Smile - it worked */ DEBUGF(" :) pts<=time time) { /* Hmm */ DEBUGF(" :\\ pts>time\n"); } if (pts >= nextpts) { /* Weird - probably because of encoded order & tends to be right * anyway if other criteria are met */ DEBUGF(" :p pts>=next pts\n"); } if (time >= nextpts) { /* Ugh */ DEBUGF(" :( time>=nextpts\n"); } } #endif return pos; } static void prepare_audio(uint32_t time) { off_t pos; if (!str_send_msg(&audio_str, STREAM_NEEDS_SYNC, time)) { DEBUGF("Audio was ready\n"); return; } pos = mpeg_parser_seek_PTS(time, audio_str.id); str_send_msg(&audio_str, STREAM_RESET, 0); str_parser.parms.sd.time = time; str_parser.parms.sd.sk.pos = pos; str_parser.parms.sd.sk.len = 1024*1024; str_parser.parms.sd.sk.dir = SSCAN_FORWARD; str_send_msg(&audio_str, STREAM_SYNC, (intptr_t)&str_parser.parms.sd); } /* This function demuxes the streams and gives the next stream data * pointer. * * STREAM_PM_STREAMING is for operation during playback. If the nescessary * data and worst-case lookahead margin is not available, the stream is * registered for notification when the data becomes available. If parsing * extends beyond the end of the file or the end of stream marker is reached, * STREAM_DATA_END is returned and the stream state changed to SSTATE_EOS. * * STREAM_PM_RANDOM_ACCESS is for operation when not playing such as seeking. * If the file cache misses for the current position + lookahead, it will be * loaded from disk. When the specified limit is reached, STREAM_DATA_END is * returned. * * The results from one mode may be used as input to the other. Random access * requires cooperation amongst threads to avoid evicting another stream's * data. */ static int parse_demux(struct stream *str, enum stream_parse_mode type) { #define INC_BUF(offset) \ ({ off_t _o = (offset); \ str->hdr.win_right += _o; \ if ((p += _o) >= disk_buf.end) \ p -= disk_buf.size; }) static const int mpeg1_skip_table[16] = { 0, 0, 4, 9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; uint8_t *p = str->curr_packet_end; str->pkt_flags = 0; while (1) { uint8_t *header; unsigned id; ssize_t length, bytes; switch (type) { case STREAM_PM_STREAMING: /* Has the end been reached already? */ switch (str->state) { case SSTATE_PARSE: /* Expected case first if no jumptable */ /* Are we at the end of file? */ if (str->hdr.win_left < disk_buf.filesize) break; str_end_of_stream(str); return STREAM_DATA_END; case SSTATE_SYNC: /* Is sync at the end of file? */ if (str->hdr.win_right < disk_buf.filesize) break; str_end_of_stream(str); /* Fall-through */ case SSTATE_END: return STREAM_DATA_END; } if (!disk_buf_is_data_ready(&str->hdr, MIN_BUFAHEAD)) { /* This data range is not buffered yet - register stream to * be notified when it becomes available. Stream is obliged * to enter a TSTATE_DATA state if it must wait. */ int res = str_next_data_not_ready(str); if (res != STREAM_OK) return res; } break; /* STREAM_PM_STREAMING: */ case STREAM_PM_RANDOM_ACCESS: str->hdr.pos = disk_buf_lseek(str->hdr.pos, SEEK_SET); if (str->hdr.pos < 0 || str->hdr.pos >= str->hdr.limit || disk_buf_getbuffer(MIN_BUFAHEAD, &p, NULL, NULL) <= 0) { str_end_of_stream(str); return STREAM_DATA_END; } str->state = SSTATE_SYNC; str->hdr.win_left = str->hdr.pos; str->curr_packet = NULL; str->curr_packet_end = p; break; /* STREAM_PM_RANDOM_ACCESS: */ } if (str->state == SSTATE_SYNC) { /* Scanning for start code */ if (!CMP_3_CONST(p, PACKET_START_CODE_PREFIX)) { INC_BUF(1); continue; } } /* Found a start code - enter parse state */ str->state = SSTATE_PARSE; /* Pack header, skip it */ if (CMP_4_CONST(p, PACK_START_CODE)) { /* Max lookahead: 14 */ if ((p[4] & 0xc0) == 0x40) /* mpeg-2 */ { /* Max delta: 14 + 7 = 21 */ /* Skip pack header and any stuffing bytes*/ bytes = 14 + (p[13] & 7); } else if ((p[4] & 0xf0) == 0x20) /* mpeg-1 */ { bytes = 12; } else /* unknown - skip it */ { DEBUGF("weird pack header!\n"); bytes = 5; } INC_BUF(bytes); } /* System header, parse and skip it - 6 bytes + size */ if (CMP_4_CONST(p, SYSTEM_HEADER_START_CODE)) { /* Skip start code */ /* Max Delta = 65535 + 6 = 65541 */ bytes = 6 + ((p[4] << 8) | p[5]); INC_BUF(bytes); } /* Packet header, parse it */ if (!CMP_3_CONST(p, PACKET_START_CODE_PREFIX)) { /* Problem? Meh...probably not but just a corrupted section. * Try to resync the parser which will probably succeed. */ DEBUGF("packet start code prefix not found: 0x%02x\n" " wl:%jd wr:%jd\n" " p:%p cp:%p cpe:%p\n" " dbs:%p dbe:%p dbt:%p\n", str->id, (intmax_t) str->hdr.win_left, (intmax_t) str->hdr.win_right, p, str->curr_packet, str->curr_packet_end, disk_buf.start, disk_buf.end, disk_buf.tail); str->state = SSTATE_SYNC; INC_BUF(1); /* Next byte - this one's no good */ continue; } /* We retrieve basic infos */ /* Maximum packet length: 6 + 65535 = 65541 */ id = p[3]; length = ((p[4] << 8) | p[5]) + 6; if (id != str->id) { switch (id) { case MPEG_STREAM_PROGRAM_END: /* end of stream */ str_end_of_stream(str); DEBUGF("MPEG program end: 0x%02x\n", str->id); return STREAM_DATA_END; case MPEG_STREAM_PACK_HEADER: case MPEG_STREAM_SYSTEM_HEADER: /* These shouldn't be here - no increment or resync * since we'll pick it up above. */ continue; default: /* It's not the packet we're looking for, skip it */ INC_BUF(length); continue; } } /* Ok, it's our packet */ header = p; if ((header[6] & 0xc0) == 0x80) /* mpeg2 */ { /* Max Lookahead: 18 */ /* Min length: 9 */ /* Max length: 9 + 255 = 264 */ length = 9 + header[8]; /* header points to the mpeg2 pes header */ if ((header[7] & 0x80) != 0) { /* header has a pts */ uint32_t pts = read_pts(header, 9); if (pts != INVALID_TIMESTAMP) { str->pts = pts; #if 0 /* DTS isn't used for anything since things just get decoded ASAP but keep the code around */ if (STREAM_IS_VIDEO(id)) { /* Video stream - header may have a dts as well */ str->dts = pts; if (header[7] & 0x40) != 0x00) { pts = read_pts(header, 14); if (pts != INVALID_TIMESTAMP) str->dts = pts; } } #endif str->pkt_flags |= PKT_HAS_TS; } } } else /* mpeg1 */ { /* Max lookahead: 24 + 2 + 9 = 35 */ /* Max len_skip: 24 + 2 = 26 */ /* Min length: 7 */ /* Max length: 24 + 2 + 9 = 35 */ off_t len_skip; uint8_t * ptsbuf; length = 7; while (header[length - 1] == 0xff) { if (++length > 23) { DEBUGF("Too much stuffing" ); break; } } if ((header[length - 1] & 0xc0) == 0x40) length += 2; len_skip = length; length += mpeg1_skip_table[header[length - 1] >> 4]; /* Header points to the mpeg1 pes header */ ptsbuf = header + len_skip; if ((ptsbuf[-1] & 0xe0) == 0x20 && TS_CHECK_MARKERS(ptsbuf, -1)) { /* header has a pts */ uint32_t pts = read_pts(ptsbuf, -1); if (pts != INVALID_TIMESTAMP) { str->pts = pts; #if 0 /* DTS isn't used for anything since things just get decoded ASAP but keep the code around */ if (STREAM_IS_VIDEO(id)) { /* Video stream - header may have a dts as well */ str->dts = pts; if (ptsbuf[-1] & 0xf0) == 0x30) { pts = read_pts(ptsbuf, 4); if (pts != INVALID_TIMESTAMP) str->dts = pts; } } #endif str->pkt_flags |= PKT_HAS_TS; } } } p += length; /* Max bytes: 6 + 65535 - 7 = 65534 */ bytes = 6 + (header[4] << 8) + header[5] - length; str->curr_packet = p; str->curr_packet_end = p + bytes; str->hdr.win_left = str->hdr.win_right + length; str->hdr.win_right = str->hdr.win_left + bytes; if (str->hdr.win_right > disk_buf.filesize) { /* No packet that exceeds end of file can be valid */ str_end_of_stream(str); return STREAM_DATA_END; } return STREAM_OK; } /* end while */ #undef INC_BUF } /* This simply reads data from the file one page at a time and returns a * pointer to it in the buffer. */ static int parse_elementary(struct stream *str, enum stream_parse_mode type) { uint8_t *p; ssize_t len = 0; str->pkt_flags = 0; switch (type) { case STREAM_PM_STREAMING: /* Has the end been reached already? */ if (str->state == SSTATE_END) return STREAM_DATA_END; /* Are we at the end of file? */ if (str->hdr.win_left >= disk_buf.filesize) { str_end_of_stream(str); return STREAM_DATA_END; } if (!disk_buf_is_data_ready(&str->hdr, MIN_BUFAHEAD)) { /* This data range is not buffered yet - register stream to * be notified when it becomes available. Stream is obliged * to enter a TSTATE_DATA state if it must wait. */ int res = str_next_data_not_ready(str); if (res != STREAM_OK) return res; } len = DISK_BUF_PAGE_SIZE; if ((size_t)(str->hdr.win_right + len) > (size_t)disk_buf.filesize) len = disk_buf.filesize - str->hdr.win_right; if (len <= 0) { str_end_of_stream(str); return STREAM_DATA_END; } p = str->curr_packet_end; if (p >= disk_buf.end) p -= disk_buf.size; break; /* STREAM_PM_STREAMING: */ case STREAM_PM_RANDOM_ACCESS: str->hdr.pos = disk_buf_lseek(str->hdr.pos, SEEK_SET); len = disk_buf_getbuffer(DISK_BUF_PAGE_SIZE, &p, NULL, NULL); if (len <= 0 || str->hdr.pos < 0 || str->hdr.pos >= str->hdr.limit) { str_end_of_stream(str); return STREAM_DATA_END; } break; /* STREAM_PM_RANDOM_ACCESS: */ } str->state = SSTATE_PARSE; str->curr_packet = p; str->curr_packet_end = p + len; str->hdr.win_left = str->hdr.win_right; str->hdr.win_right = str->hdr.win_left + len; return STREAM_OK; } bool parser_prepare_image(uint32_t time) { struct stream_scan sk; int tries; int result; stream_scan_init(&sk); if (!str_send_msg(&video_str, STREAM_NEEDS_SYNC, time)) { DEBUGF("Image was ready\n"); return true; /* Should already have the image */ } #ifdef HAVE_ADJUSTABLE_CPU_FREQ rb->cpu_boost(true); /* No interference with trigger_cpu_boost */ #endif str_send_msg(&video_str, STREAM_RESET, 0); sk.pos = parser_can_seek() ? mpeg_parser_seek_PTS(time, video_str.id) : 0; sk.len = sk.pos; sk.dir = SSCAN_REVERSE; tries = 1; try_again: if (mpeg_parser_scan_start_code(&sk, MPEG_START_GOP)) { DEBUGF("GOP found at: %jd\n", (intmax_t) sk.pos); unsigned id = mpeg_parser_scan_pes(&sk); if (id != video_str.id && sk.pos > 0) { /* Not part of our stream */ DEBUGF(" wrong stream: 0x%02x\n", id); goto try_again; } /* This will hit the PES header since it's known to be there */ uint32_t pts = mpeg_parser_scan_pts(&sk, id); if (pts == INVALID_TIMESTAMP || pts > time) { DEBUGF(" wrong timestamp: %u\n", (unsigned)pts); goto try_again; } } str_parser.parms.sd.time = time; str_parser.parms.sd.sk.pos = MAX(sk.pos, 0); str_parser.parms.sd.sk.len = 1024*1024; str_parser.parms.sd.sk.dir = SSCAN_FORWARD; DEBUGF("thumb pos:%jd len:%ld\n", (intmax_t) str_parser.parms.sd.sk.pos, (long)str_parser.parms.sd.sk.len); result = str_send_msg(&video_str, STREAM_SYNC, (intptr_t)&str_parser.parms.sd); if (result != STREAM_PERFECT_MATCH) { /* Two tries should be all that is nescessary to find the exact frame * if the first GOP actually started later than the timestamp - the * GOP just prior must then start on or earlier. */ if (++tries <= 2) goto try_again; } #ifdef HAVE_ADJUSTABLE_CPU_FREQ rb->cpu_boost(false); #endif return result > STREAM_OK; } /* Seek parser to the specified time and return absolute time. * No actual hard stuff is performed here. That's done when streaming is * about to begin or something from the current position is requested */ uint32_t parser_seek_time(uint32_t time) { if (!parser_can_seek()) time = 0; else if (time > str_parser.duration) time = str_parser.duration; str_parser.last_seek_time = time + str_parser.start_pts; return str_parser.last_seek_time; } void parser_prepare_streaming(void) { struct stream_window sw; DEBUGF("parser_prepare_streaming\n"); /* Prepare initial video frame */ parser_prepare_image(str_parser.last_seek_time); /* Sync audio stream */ if (audio_str.start_pts != INVALID_TIMESTAMP) prepare_audio(str_parser.last_seek_time); /* Prequeue some data and set buffer window */ if (!stream_get_window(&sw)) sw.left = sw.right = disk_buf.filesize; DEBUGF(" swl:%jd swr:%jd\n", (intmax_t) sw.left, (intmax_t) sw.right); if (sw.right > disk_buf.filesize - 4*MIN_BUFAHEAD) sw.right = disk_buf.filesize - 4*MIN_BUFAHEAD; disk_buf_prepare_streaming(sw.left, sw.right - sw.left + 4*MIN_BUFAHEAD); } int parser_init_stream(void) { if (disk_buf.in_file < 0) return STREAM_ERROR; /* TODO: Actually find which streams are available */ audio_str.id = MPEG_STREAM_AUDIO_FIRST; video_str.id = MPEG_STREAM_VIDEO_FIRST; /* Try to pull a video PES - if not found, try video init anyway which * should succeed if it really is a video-only stream */ video_str.hdr.pos = 0; video_str.hdr.limit = 256*1024; if (parse_demux(&video_str, STREAM_PM_RANDOM_ACCESS) == STREAM_OK) { /* Found a video packet - assume program stream */ str_parser.format = STREAM_FMT_MPEG_PS; str_parser.next_data = parse_demux; } else { /* No PES element found - assume video elementary stream */ str_parser.format = STREAM_FMT_MPV; str_parser.next_data = parse_elementary; } if (!init_video_info()) { /* Cannot determine video size, etc. */ parser_init_state(); return STREAM_UNSUPPORTED; } if (str_parser.format == STREAM_FMT_MPEG_PS) { /* Initalize start_pts and end_pts with the length (in 45kHz units) of * the movie. INVALID_TIMESTAMP if the time could not be determined */ if (!init_times(&video_str) || !check_times(&video_str)) { /* Must have video at least */ parser_init_state(); return STREAM_UNSUPPORTED; } str_parser.flags |= STREAMF_CAN_SEEK; if (init_times(&audio_str)) { /* Audio will be part of playback pool */ stream_add_stream(&audio_str); if (check_times(&audio_str)) { /* Overall duration is maximum span */ str_parser.start_pts = MIN(audio_str.start_pts, video_str.start_pts); str_parser.end_pts = MAX(audio_str.end_pts, video_str.end_pts); } else { /* Bad times on audio - use video times */ str_parser.start_pts = video_str.start_pts; str_parser.end_pts = video_str.end_pts; /* Questionable: could use bitrate seek and match video to that */ audio_str.start_pts = video_str.start_pts; audio_str.end_pts = video_str.end_pts; } } else { /* No audio stream - use video only */ str_parser.start_pts = video_str.start_pts; str_parser.end_pts = video_str.end_pts; } str_parser.last_seek_time = str_parser.start_pts; } else { /* There's no way to handle times on this without a full file * scan */ audio_str.start_pts = INVALID_TIMESTAMP; audio_str.end_pts = INVALID_TIMESTAMP; video_str.start_pts = 0; video_str.end_pts = INVALID_TIMESTAMP; str_parser.start_pts = 0; str_parser.end_pts = INVALID_TIMESTAMP; } /* Add video to playback pool */ stream_add_stream(&video_str); /* Cache duration - it's used very often */ str_parser.duration = str_parser.end_pts - str_parser.start_pts; DEBUGF("Movie info:\n" " size:%dx%d\n" " start:%u\n" " end:%u\n" " duration:%u\n", str_parser.dims.w, str_parser.dims.h, (unsigned)str_parser.start_pts, (unsigned)str_parser.end_pts, (unsigned)str_parser.duration); return STREAM_OK; } void parser_close_stream(void) { stream_remove_streams(); parser_init_state(); } bool parser_init(void) { parser_init_state(); return true; }