sample_muxer: added support for WebVTT chapters
Change-Id: Ic5ab8097c0981ef300eadc4a3c151f63b2aad81d
diff --git a/sample_muxer_metadata.cc b/sample_muxer_metadata.cc
index 4066670..c3a2e3f 100644
--- a/sample_muxer_metadata.cc
+++ b/sample_muxer_metadata.cc
@@ -16,6 +16,9 @@
}
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 @@
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 @@
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) {
