Initial community commit

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 &timestamp_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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