*/
+#include "dcpomatic_log.h"
extern "C" {
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
using std::string;
using std::cout;
using std::max;
+using std::vector;
using boost::shared_ptr;
using boost::optional;
+/* This is how many frames from the start of any video that we will examine to see if we
+ * can spot soft 2:3 pull-down ("telecine").
+ */
+static const int PULLDOWN_CHECK_FRAMES = 16;
+
+
/** @param job job that the examiner is operating in, or 0 */
FFmpegExaminer::FFmpegExaminer (shared_ptr<const FFmpegContent> c, shared_ptr<Job> job)
: FFmpeg (c)
, _video_length (0)
, _need_video_length (false)
+ , _pulldown (false)
{
/* Find audio and subtitle streams */
/* Run through until we find:
* - the first video.
* - the first audio for each stream.
+ * - the top-field-first and repeat-first-frame values ("temporal_reference") for the first PULLDOWN_CHECK_FRAMES video frames.
*/
int64_t const len = _file_group.length ();
+ /* A string which we build up to describe the top-field-first and repeat-first-frame values for the first few frames.
+ * It would be nicer to use something like vector<bool> here but we want to search the array for a pattern later,
+ * and a string seems a reasonably neat way to do that.
+ */
+ string temporal_reference;
while (true) {
int r = av_read_frame (_format_context, &_packet);
if (r < 0) {
AVCodecContext* context = _format_context->streams[_packet.stream_index]->codec;
if (_video_stream && _packet.stream_index == _video_stream.get()) {
- video_packet (context);
+ video_packet (context, temporal_reference);
}
bool got_all_audio = true;
av_packet_unref (&_packet);
- if (_first_video && got_all_audio) {
+ if (_first_video && got_all_audio && temporal_reference.size() >= PULLDOWN_CHECK_FRAMES) {
/* All done */
break;
}
DCPOMATIC_ASSERT (fabs (*_rotation - 90 * round (*_rotation / 90)) < 2);
}
+
+ LOG_GENERAL("Temporal reference was %1", temporal_reference);
+ if (temporal_reference.find("T2T3B2B3T2T3B2B3") || temporal_reference.find("B2B3T2T3B2B3T2T3")) {
+ /* The magical sequence (taken from mediainfo) suggests that 2:3 pull-down is in use */
+ _pulldown = true;
+ LOG_GENERAL_NC("Suggest that this may be 2:3 pull-down (soft telecine)");
+ }
+
+#ifdef DCPOMATIC_VARIANT_SWAROOP
+ AVDictionaryEntry* e = av_dict_get (_format_context->metadata, SWAROOP_ID_TAG, 0, 0);
+ if (e) {
+ _id = e->value;
+ }
+#endif
}
+
+/** @param temporal_reference A string to which we should add two characters per frame;
+ * the first is T or B depending on whether it's top- or bottom-field first,
+ * ths seconds is 3 or 2 depending on whether "repeat_pict" is true or not.
+ */
void
-FFmpegExaminer::video_packet (AVCodecContext* context)
+FFmpegExaminer::video_packet (AVCodecContext* context, string& temporal_reference)
{
DCPOMATIC_ASSERT (_video_stream);
- if (_first_video && !_need_video_length) {
+ if (_first_video && !_need_video_length && temporal_reference.size() >= PULLDOWN_CHECK_FRAMES) {
return;
}
_format_context->streams[_video_stream.get()]
).get_value_or (ContentTime ()).frames_round (video_frame_rate().get ());
}
+ if (temporal_reference.size() < PULLDOWN_CHECK_FRAMES) {
+ temporal_reference += (_frame->top_field_first ? "T" : "B");
+ temporal_reference += (_frame->repeat_pict ? "3" : "2");
+ }
}
}