diff options
Diffstat (limited to 'Src/nsavi/seektable.cpp')
| -rw-r--r-- | Src/nsavi/seektable.cpp | 177 |
1 files changed, 177 insertions, 0 deletions
diff --git a/Src/nsavi/seektable.cpp b/Src/nsavi/seektable.cpp new file mode 100644 index 00000000..494674e9 --- /dev/null +++ b/Src/nsavi/seektable.cpp @@ -0,0 +1,177 @@ +#include "seektable.h" +#include "demuxer.h" + +static int GetStreamNumber(uint32_t id) +{ + char *stream_data = (char *)(&id); + if (!isxdigit(stream_data[0]) || !isxdigit(stream_data[1])) + return -1; + + stream_data[2] = 0; + int stream_number = strtoul(stream_data, 0, 16); + return stream_number; +} + +nsavi::SeekTable::SeekTable(int stream_number, bool require_keyframes, const nsavi::HeaderList *header_list) +: header_list(header_list), stream_number(stream_number), require_keyframes(require_keyframes), super_index(0), indices_processed(0), super_index_duration(0) +{ + stream = header_list->stream_list[stream_number].stream_header; + const nsavi::INDX *index = header_list->stream_list[stream_number].stream_index; + if (index) + { + if (index->index_type == nsavi::indx_type_master) + { + super_index = (nsavi::AVISUPERINDEX *)index; + } + else if (index->index_type == nsavi::indx_type_chunk) + { + AddIndex(index, 0); + } + } +} + +nsavi::SeekTable::~SeekTable() +{ +} + +const nsavi::SeekEntry *nsavi::SeekTable::GetSeekPoint(int ×tamp_ms, int current_ms, int seek_direction) +{ + int last_time = 0; + const nsavi::SeekEntry *last_entry = 0; + + // TODO: binary search + for (SeekEntries::iterator itr=seek_entries.begin();itr!=seek_entries.end();itr++) + { + if (itr->first > timestamp_ms) + { + if (seek_direction == SEEK_FORWARD && current_ms >= last_time) + { + itr++; + if (itr != seek_entries.end()) + { + last_entry = &itr->second; + last_time = itr->first; + } + else + { + return 0; + } + } + + timestamp_ms = last_time; + return last_entry; + + } + last_entry = &itr->second; + last_time = itr->first; + + } + if (seek_direction == SEEK_FORWARD && current_ms >= last_time) + { + return 0; + } + else + { + timestamp_ms = last_time; + return last_entry; + } + +} + +void nsavi::SeekTable::AddIndex(const IDX1 *index) +{ + // TODO: calculate total bytes at the same time, so we can get a more accurate bitrate + data_processed[index] = true; + uint64_t total_time = 0; + uint64_t stream_rate = (uint64_t)stream->rate; + + //if (!require_keyframes) + // seek_entries.reserve(seek_entries.size() + index->index_count); + + for (uint32_t i=0;i!=index->index_count;i++) + { + const nsavi::IDX1_INDEX &this_index = index->indices[i]; + int this_stream_number = GetStreamNumber(this_index.chunk_id); + if (this_stream_number == stream_number && (!require_keyframes || this_index.flags & nsavi::idx1_flags_keyframe)) + { + int timestamp = (int)(total_time * 1000ULL / stream_rate); + SeekEntry &entry = seek_entries[timestamp]; +#ifdef SEEK_TABLE_STORE_CHUNK_HEADER + entry.chunk_id = this_index.chunk_id; + entry.chunk_size = this_index.chunk_size; +#endif + entry.file_position = this_index.offset; + entry.stream_time = total_time; + entry.timestamp = timestamp; + entry.absolute = false; + } + if (this_stream_number == stream_number && !(this_index.flags & nsavi::idx1_flags_no_duration)) + { + if (stream->sample_size) + { + uint64_t samples = this_index.chunk_size / stream->sample_size; + total_time += stream->scale * samples; + } + else + total_time += stream->scale; + } + } +} + +void nsavi::SeekTable::AddIndex(const INDX *index, uint64_t start_time) +{ + if (index->index_type == nsavi::indx_type_chunk) + { + const nsavi::AVISTDINDEX *chunk_index = (nsavi::AVISTDINDEX *)index; + + //if (!require_keyframes) + // seek_entries.reserve(seek_entries.size() + chunk_index->indx.number_of_entries); + + + start_time *= stream->scale; + + uint64_t stream_rate = (uint64_t)stream->rate; + for (uint32_t i=0;i!=chunk_index->indx.number_of_entries;i++) + { + const INDX_CHUNK_ENTRY &this_index = chunk_index->entries[i]; + if (!require_keyframes || !(this_index.size & 0x80000000)) + { + int timestamp = (int)(start_time * 1000ULL / stream_rate); + SeekEntry &entry = seek_entries[timestamp]; +#ifdef SEEK_TABLE_STORE_CHUNK_HEADER + entry.chunk_id = chunk_index->indx.chunk_id; + entry.chunk_size = this_index.size & ~0x80000000; +#endif + entry.file_position = chunk_index->base_offset + this_index.offset; + entry.stream_time = start_time; + entry.timestamp = timestamp; + entry.absolute = true; + } + + if (stream->sample_size) + { + uint64_t samples = this_index.size / stream->sample_size; + start_time += stream->scale * samples; + } + else + start_time += stream->scale; + } + } +} + +bool nsavi::SeekTable::GetIndexLocation(int timestamp, uint64_t *position, uint64_t *start_time) +{ + // TODO: use timestamp more effectively + if (super_index) + { + for (uint32_t i=indices_processed;i!=super_index->indx.number_of_entries;i++) + { + indices_processed++; + *start_time = super_index_duration; + super_index_duration += super_index->entries[i].duration; + *position = super_index->entries[i].offset; + return true; + } + } + return false; +}
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