[MP4] Allow not to generate 'sidx' box for single-segment too

I.e. the flag --generate_sidx_in_media_segments,
--nogenerate_sidx_in_media_segments work for both single-segment
and multi-segment mode with this change.

Related to #862.

Change-Id: Icd27fd00e8e036ba0c4709b48650372429cc0351

docs/source/options/mp4_output_options.rst

@@ -12,6 +12,8 @@ MP4 output options
 --generate_sidx_in_media_segments
 --nogenerate_sidx_in_media_segments
 
-    For MP4 with DASH live profile only: Indicates whether to generate 'sidx'
-    box in media segments. Note that it is reuqired by spec if segment template
-    contains $Time$ specifier.
+    Indicates whether to generate 'sidx' box in media segments. Note
+    that it is required for DASH on-demand profile (not using segment
+    template).
+
+    Default enabled.

packager/app/muxer_flags.cc

@@ -36,9 +36,9 @@ DEFINE_bool(fragment_sap_aligned,
             "implies segment_sap_aligned.");
 DEFINE_bool(generate_sidx_in_media_segments,
             true,
-            "For ISO BMFF with DASH live profile only. Indicates whether to "
-            "generate 'sidx' box in media segments. Note that it is required "
-            "by spec if segment template contains $Time$ specifier.");
+            "Indicates whether to generate 'sidx' box in media segments. Note "
+            "that it is required for DASH on-demand profile (not using segment "
+            "template).");
 DEFINE_string(temp_dir,
               "",
               "Specify a directory in which to store temporary (intermediate) "

packager/media/formats/mp4/single_segment_segmenter.cc

@@ -45,14 +45,18 @@ bool SingleSegmentSegmenter::GetIndexRange(size_t* offset, size_t* size) {
   // Index range is right after init range so the offset must be the size of
   // ftyp and moov.
   *offset = ftyp()->ComputeSize() + moov()->ComputeSize();
-  *size = vod_sidx_->ComputeSize();
+  *size = options().mp4_params.generate_sidx_in_media_segments
+              ? vod_sidx_->ComputeSize()
+              : 0;
   return true;
 }
 
 std::vector<Range> SingleSegmentSegmenter::GetSegmentRanges() {
   std::vector<Range> ranges;
-  uint64_t next_offset =
-      ftyp()->ComputeSize() + moov()->ComputeSize() + vod_sidx_->ComputeSize() +
+  uint64_t next_offset = ftyp()->ComputeSize() + moov()->ComputeSize() +
+                         (options().mp4_params.generate_sidx_in_media_segments
+                              ? vod_sidx_->ComputeSize()
+                              : 0) +
                          vod_sidx_->first_offset;
   for (const SegmentReference& segment_reference : vod_sidx_->references) {
     Range r;
@@ -111,7 +115,10 @@ Status SingleSegmentSegmenter::DoFinalize() {
   std::unique_ptr<BufferWriter> buffer(new BufferWriter());
   ftyp()->Write(buffer.get());
   moov()->Write(buffer.get());
+
+  if (options().mp4_params.generate_sidx_in_media_segments)
     vod_sidx_->Write(buffer.get());
+
   Status status = buffer->WriteToFile(file.get());
   if (!status.ok())
     return status;

packager/media/formats/mp4/single_segment_segmenter.h

@@ -24,8 +24,7 @@ namespace mp4 {
 /// may not match the requested duration exactly, but will be approximated. That
 /// is, the Segmenter tries to end subsegment/fragment at the first sample with
 /// overall subsegment/fragment duration not smaller than defined duration and
-/// yet meet SAP requirements. SingleSegmentSegmenter ignores @b
-/// MuxerOptions.mp4_params.generate_sidx_in_media_segments.
+/// yet meet SAP requirements.
 class SingleSegmentSegmenter : public Segmenter {
  public:
   SingleSegmentSegmenter(const MuxerOptions& options,

packager/packager.cc

@@ -351,6 +351,14 @@ Status ValidateParams(const PackagingParams& packaging_params,
                   "(not using segment_template).");
   }
 
+  if (on_demand_dash_profile &&
+      !packaging_params.mpd_params.mpd_output.empty() &&
+      !packaging_params.mp4_output_params.generate_sidx_in_media_segments) {
+    return Status(error::UNIMPLEMENTED,
+                  "--generate_sidx_in_media_segments is required for DASH "
+                  "on-demand profile (not using segment_template).");
+  }
+
   return Status::OK;
 }