Diffstat (limited to 'core/multimedia/opieplayer/libmpeg3/video/seek.c') (more/less context) (ignore whitespace changes)
| -rw-r--r-- | core/multimedia/opieplayer/libmpeg3/video/seek.c | 233 |
1 files changed, 233 insertions, 0 deletions
diff --git a/core/multimedia/opieplayer/libmpeg3/video/seek.c b/core/multimedia/opieplayer/libmpeg3/video/seek.c new file mode 100644 index 0000000..04faba4 --- a/dev/null +++ b/core/multimedia/opieplayer/libmpeg3/video/seek.c @@ -0,0 +1,233 @@ +#include "../mpeg3private.h" +#include "../mpeg3protos.h" +#include "mpeg3video.h" +#include <stdlib.h> +#include <string.h> + +unsigned int mpeg3bits_next_startcode(mpeg3_bits_t* stream) +{ +/* Perform forwards search */ + mpeg3bits_byte_align(stream); + +/* Perform search */ + while((mpeg3bits_showbits32_noptr(stream) >> 8) != MPEG3_PACKET_START_CODE_PREFIX && + !mpeg3bits_eof(stream)) + { + mpeg3bits_getbyte_noptr(stream); + } + return mpeg3bits_showbits32_noptr(stream); +} + +/* Line up on the beginning of the next code. */ +int mpeg3video_next_code(mpeg3_bits_t* stream, unsigned int code) +{ + while(!mpeg3bits_eof(stream) && + mpeg3bits_showbits32_noptr(stream) != code) + { + mpeg3bits_getbyte_noptr(stream); + } + return mpeg3bits_eof(stream); +} + +/* Line up on the beginning of the previous code. */ +int mpeg3video_prev_code(mpeg3_bits_t* stream, unsigned int code) +{ + while(!mpeg3bits_bof(stream) && + mpeg3bits_showbits_reverse(stream, 32) != code) + { + mpeg3bits_getbits_reverse(stream, 8); + } + return mpeg3bits_bof(stream); +} + +long mpeg3video_goptimecode_to_frame(mpeg3video_t *video) +{ +/* printf("mpeg3video_goptimecode_to_frame %d %d %d %d %f\n", */ +/* video->gop_timecode.hour, video->gop_timecode.minute, video->gop_timecode.second, video->gop_timecode.frame, video->frame_rate); */ + return (long)(video->gop_timecode.hour * 3600 * video->frame_rate + + video->gop_timecode.minute * 60 * video->frame_rate + + video->gop_timecode.second * video->frame_rate + + video->gop_timecode.frame) - 1 - video->first_frame; +} + +int mpeg3video_match_refframes(mpeg3video_t *video) +{ + unsigned char *dst, *src; + int i, j, size; + + for(i = 0; i < 3; i++) + { + if(video->newframe[i]) + { + if(video->newframe[i] == video->refframe[i]) + { + src = video->refframe[i]; + dst = video->oldrefframe[i]; + } + else + { + src = video->oldrefframe[i]; + dst = video->refframe[i]; + } + + if(i == 0) + size = video->coded_picture_width * video->coded_picture_height + 32 * video->coded_picture_width; + else + size = video->chrom_width * video->chrom_height + 32 * video->chrom_width; + + memcpy(dst, src, size); + } + } + return 0; +} + +int mpeg3video_seek(mpeg3video_t *video) +{ + long this_gop_start; + int result = 0; + int back_step; + int attempts; + mpeg3_t *file = video->file; + mpeg3_bits_t *vstream = video->vstream; + double percentage; + long frame_number; + int match_refframes = 1; + +/* Seek to a percentage */ + if(video->percentage_seek >= 0) + { + percentage = video->percentage_seek; + video->percentage_seek = -1; + mpeg3bits_seek_percentage(vstream, percentage); +// Go to previous I-frame + mpeg3bits_start_reverse(vstream); + result = mpeg3video_prev_code(vstream, MPEG3_GOP_START_CODE); + if(!result) mpeg3bits_getbits_reverse(vstream, 32); + mpeg3bits_start_forward(vstream); + + if(mpeg3bits_tell_percentage(vstream) < 0) mpeg3bits_seek_percentage(vstream, 0); + +// Read up to the correct percentage + result = 0; + while(!result && mpeg3bits_tell_percentage(vstream) < percentage) + { + result = mpeg3video_read_frame_backend(video, 0); + if(match_refframes) + mpeg3video_match_refframes(video); + match_refframes = 0; + } + } + else +/* Seek to a frame */ + if(video->frame_seek >= 0) + { + frame_number = video->frame_seek; + video->frame_seek = -1; + if(frame_number < 0) frame_number = 0; + if(frame_number > video->maxframe) frame_number = video->maxframe; + +/* Seek to start of file */ + if(frame_number < 16) + { + video->repeat_count = video->current_repeat = 0; + mpeg3bits_seek_start(vstream); + video->framenum = 0; + result = mpeg3video_drop_frames(video, frame_number - video->framenum); + } + else + { +/* Seek to an I frame. */ + if((frame_number < video->framenum || frame_number - video->framenum > MPEG3_SEEK_THRESHOLD)) + { +/* Elementary stream */ + if(file->is_video_stream) + { + mpeg3_t *file = video->file; + mpeg3_vtrack_t *track = video->track; + long byte = (long)((float)(mpeg3demuxer_total_bytes(vstream->demuxer) / + track->total_frames) * + frame_number); + long minimum = 65535; + int done = 0; + +//printf("seek elementary %d\n", frame_number); +/* Get GOP just before frame */ + do + { + result = mpeg3bits_seek_byte(vstream, byte); + mpeg3bits_start_reverse(vstream); + if(!result) result = mpeg3video_prev_code(vstream, MPEG3_GOP_START_CODE); + mpeg3bits_start_forward(vstream); + mpeg3bits_getbits(vstream, 8); + if(!result) result = mpeg3video_getgophdr(video); + this_gop_start = mpeg3video_goptimecode_to_frame(video); + +//printf("wanted %ld guessed %ld byte %ld result %d\n", frame_number, this_gop_start, byte, result); + if(labs(this_gop_start - frame_number) >= labs(minimum)) + done = 1; + else + { + minimum = this_gop_start - frame_number; + byte += (long)((float)(frame_number - this_gop_start) * + (float)(mpeg3demuxer_total_bytes(vstream->demuxer) / + track->total_frames)); + if(byte < 0) byte = 0; + } + }while(!result && !done); + +//printf("wanted %d guessed %d\n", frame_number, this_gop_start); + if(!result) + { + video->framenum = this_gop_start; + result = mpeg3video_drop_frames(video, frame_number - video->framenum); + } + } + else +/* System stream */ + { + mpeg3bits_seek_time(vstream, (double)frame_number / video->frame_rate); + percentage = mpeg3bits_tell_percentage(vstream); +//printf("seek frame %ld percentage %f byte %ld\n", frame_number, percentage, mpeg3bits_tell(vstream)); + mpeg3bits_start_reverse(vstream); + mpeg3video_prev_code(vstream, MPEG3_GOP_START_CODE); + mpeg3bits_getbits_reverse(vstream, 32); + mpeg3bits_start_forward(vstream); +//printf("seek system 1 %f\n", (double)frame_number / video->frame_rate); + + while(!result && mpeg3bits_tell_percentage(vstream) < percentage) + { + result = mpeg3video_read_frame_backend(video, 0); + if(match_refframes) + mpeg3video_match_refframes(video); + +//printf("seek system 2 %f %f\n", mpeg3bits_tell_percentage(vstream) / percentage); + match_refframes = 0; + } +//printf("seek system 3 %f\n", (double)frame_number / video->frame_rate); + } + + video->framenum = frame_number; + } + else +// Drop frames + { + mpeg3video_drop_frames(video, frame_number - video->framenum); + } + } + } + + return result; +} + +int mpeg3video_drop_frames(mpeg3video_t *video, long frames) +{ + int result = 0; + long frame_number = video->framenum + frames; + +/* Read the selected number of frames and skip b-frames */ + while(!result && frame_number > video->framenum) + { + result = mpeg3video_read_frame_backend(video, frame_number - video->framenum); + } + return result; +} |