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sample_muxer: added support for WebVTT chapters

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Change-Id: Ic5ab8097c0981ef300eadc4a3c151f63b2aad81d
This commit is contained in:
Matthew Heaney 2012-10-22 16:20:20 -07:00
parent c99838a5fe
commit ad54bfb572
3 changed files with 184 additions and 14 deletions
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29
sample_muxer.cpp
View File

@ -63,6 +63,8 @@ void Usage() {
"add WebVTT descriptions as metadata track\n");
printf(" -webvtt-metadata <vttfile> "
"add WebVTT subtitles as metadata track\n");
printf(" -webvtt-chapters <vttfile> "
"add WebVTT chapters as MKV chapters element\n");
}
struct MetadataFile {
@ -98,13 +100,14 @@ int ParseArgWebVTT(
metadata_files_t* metadata_files) {
int& i = *argv_index;
enum { kCount = 4 };
enum { kCount = 5 };
struct Arg { const char* name; SampleMuxerMetadata::Kind kind; };
const Arg args[kCount] = {
{ "-webvtt-subtitles", SampleMuxerMetadata::kSubtitles },
{ "-webvtt-captions", SampleMuxerMetadata::kCaptions },
{ "-webvtt-descriptions", SampleMuxerMetadata::kDescriptions },
{ "-webvtt-metadata", SampleMuxerMetadata::kMetadata }
{ "-webvtt-metadata", SampleMuxerMetadata::kMetadata },
{ "-webvtt-chapters", SampleMuxerMetadata::kChapters }
};
for (int idx = 0; idx < kCount; ++idx) {
@ -147,8 +150,8 @@ int main(int argc, char* argv[]) {
uint64 max_cluster_duration = 0;
uint64 max_cluster_size = 0;
bool switch_tracks = false;
int audio_track_number = 0; // 0 tells muxer to decide.
int video_track_number = 0; // 0 tells muxer to decide.
int audio_track_number = 0; // 0 tells muxer to decide.
int video_track_number = 0; // 0 tells muxer to decide.
bool chunking = false;
const char* chunk_name = NULL;
@ -291,8 +294,8 @@ int main(int argc, char* argv[]) {
// Set Tracks element attributes
const mkvparser::Tracks* const parser_tracks = parser_segment->GetTracks();
unsigned long i = 0;
uint64 vid_track = 0; // no track added
uint64 aud_track = 0; // no track added
uint64 vid_track = 0; // no track added
uint64 aud_track = 0; // no track added
using mkvparser::Track;
@ -408,6 +411,9 @@ int main(int argc, char* argv[]) {
if (!LoadMetadataFiles(metadata_files, &metadata))
return EXIT_FAILURE;
if (!metadata.AddChapters())
return EXIT_FAILURE;
// Set Cues element attributes
mkvmuxer::Cues* const cues = muxer_segment.GetCues();
cues->set_output_block_number(output_cues_block_number);
@ -427,8 +433,7 @@ int main(int argc, char* argv[]) {
long status = cluster->GetFirst(block_entry);
if (status)
{
if (status) {
printf("\n Could not get first block of cluster.\n");
return EXIT_FAILURE;
}
@ -483,8 +488,7 @@ int main(int argc, char* argv[]) {
status = cluster->GetNext(block_entry, block_entry);
if (status)
{
if (status) {
printf("\n Could not get next block of cluster.\n");
return EXIT_FAILURE;
}
@ -498,7 +502,10 @@ int main(int argc, char* argv[]) {
if (!metadata.Write(-1))
return EXIT_FAILURE;
muxer_segment.Finalize();
if (!muxer_segment.Finalize()) {
printf("Finalization of segment failed.\n");
return EXIT_FAILURE;
}
delete [] data;
delete parser_segment;

141
sample_muxer_metadata.cc
View File

@ -16,6 +16,9 @@ bool SampleMuxerMetadata::Init(mkvmuxer::Segment* segment) {
}
bool SampleMuxerMetadata::Load(const char* file, Kind kind) {
if (kind == kChapters)
return LoadChapters(file);
mkvmuxer::uint64 track_num;
if (!AddTrack(kind, &track_num)) {
@ -26,6 +29,21 @@ bool SampleMuxerMetadata::Load(const char* file, Kind kind) {
return Parse(file, kind, track_num);
}
bool SampleMuxerMetadata::AddChapters() {
typedef cue_list_t::const_iterator iter_t;
iter_t i = chapter_cues_.begin();
const iter_t j = chapter_cues_.end();
while (i != j) {
const cue_t& chapter = *i++;
if (!AddChapter(chapter))
return false;
}
return true;
}
bool SampleMuxerMetadata::Write(mkvmuxer::int64 time_ns) {
typedef cues_set_t::iterator iter_t;
@ -49,6 +67,129 @@ bool SampleMuxerMetadata::Write(mkvmuxer::int64 time_ns) {
return true;
}
bool SampleMuxerMetadata::LoadChapters(const char* file) {
if (!chapter_cues_.empty()) {
printf("Support for more than one chapters file is not yet implemented\n");
return false;
}
cue_list_t cues;
if (!ParseChapters(file, &cues))
return false;
// TODO(matthewjheaney): support more than one chapters file
chapter_cues_.swap(cues);
return true;
}
bool SampleMuxerMetadata::ParseChapters(
const char* file,
cue_list_t* cues_ptr) {
cue_list_t& cues = *cues_ptr;
cues.clear();
libwebvtt::VttReader r;
int e = r.Open(file);
if (e) {
printf("Unable to open WebVTT file: \"%s\"\n", file);
return false;
}
libwebvtt::Parser p(&r);
e = p.Init();
if (e < 0) { // error
printf("Error parsing WebVTT file: \"%s\"\n", file);
return false;
}
libwebvtt::Time t;
t.hours = -1;
for (;;) {
cue_t c;
e = p.Parse(&c);
if (e < 0) { // error
printf("Error parsing WebVTT file: \"%s\"\n", file);
return false;
}
if (e > 0) // EOF
return true;
if (c.start_time < t) {
printf("bad WebVTT cue timestamp (out-of-order)\n");
return false;
}
if (c.stop_time < c.start_time) {
printf("bad WebVTT cue timestamp (stop < start)\n");
return false;
}
t = c.start_time;
cues.push_back(c);
}
}
bool SampleMuxerMetadata::AddChapter(const cue_t& cue) {
// TODO(matthewjheaney): support language and country
mkvmuxer::Chapter* const chapter = segment_->AddChapter();
if (chapter == NULL) {
printf("Unable to add chapter\n");
return false;
}
if (cue.identifier.empty()) {
chapter->set_id(NULL);
} else {
const char* const id = cue.identifier.c_str();
if (!chapter->set_id(id)) {
printf("Unable to set chapter id\n");
return false;
}
}
typedef libwebvtt::presentation_t time_ms_t;
const time_ms_t start_time_ms = cue.start_time.presentation();
const time_ms_t stop_time_ms = cue.stop_time.presentation();
enum { kNsPerMs = 1000000 };
const mkvmuxer::uint64 start_time_ns = start_time_ms * kNsPerMs;
const mkvmuxer::uint64 stop_time_ns = stop_time_ms * kNsPerMs;
chapter->set_time(*segment_, start_time_ns, stop_time_ns);
typedef libwebvtt::Cue::payload_t::const_iterator iter_t;
iter_t i = cue.payload.begin();
const iter_t j = cue.payload.end();
string title;
for (;;) {
title += *i++;
if (i == j)
break;
enum { kLF = '\x0A' };
title += kLF;
}
if (!chapter->add_string(title.c_str(), NULL, NULL)) {
printf("Unable to set chapter title\n");
return false;
}
return true;
}
bool SampleMuxerMetadata::AddTrack(
Kind kind,
mkvmuxer::uint64* track_num) {

28
sample_muxer_metadata.h
View File

@ -21,7 +21,8 @@ class SampleMuxerMetadata {
kSubtitles,
kCaptions,
kDescriptions,
kMetadata
kMetadata,
kChapters
};
SampleMuxerMetadata();
@ -31,10 +32,12 @@ class SampleMuxerMetadata {
bool Init(mkvmuxer::Segment* segment);
// Parse the WebVTT file |filename| having the indicated |kind|, and
// create a corresponding track in the segment. Returns false on
// error.
// create a corresponding track (or chapters element) in the
// segment. Returns false on error.
bool Load(const char* filename, Kind kind);
bool AddChapters();
// Write any WebVTT cues whose time is less or equal to |time_ns| as
// a metadata block in its corresponding track. If |time_ns| is
// negative, write all remaining cues. Returns false on error.
@ -74,6 +77,21 @@ class SampleMuxerMetadata {
};
typedef std::multiset<SortableCue> cues_set_t;
typedef std::list<cue_t> cue_list_t;
// Parse the WebVTT cues in the named |file|, returning false on
// error. We handle chapters as a special case, because they are
// stored in their own, dedicated level-1 element.
bool LoadChapters(const char* file);
// Parse the WebVTT chapters in |file| to populate |cues|. Returns
// false on error.
static bool ParseChapters(const char* file,
cue_list_t* cues);
// Adds WebVTT cue |chapter| to the chapters element of the output
// file's segment element. Returns false on error.
bool AddChapter(const cue_t& chapter);
// Add a metadata track to the segment having the indicated |kind|,
// returning the |track_num| that has been chosen for this track.
@ -105,6 +123,10 @@ class SampleMuxerMetadata {
// Set of cues ordered by time and then by track number.
cues_set_t cues_set_;
// The cues that will be used to populate the Chapters level-1
// element of the output file.
cue_list_t chapter_cues_;
// Disable copy ctor and copy assign.
SampleMuxerMetadata(const SampleMuxerMetadata&);
SampleMuxerMetadata& operator=(const SampleMuxerMetadata&);