From de94555cdc69ea566f9f8770c5e3f26af10a67ca Mon Sep 17 00:00:00 2001
From: Yondon Fu <yondon.fu@gmail.com>
Date: Sat, 20 Jan 2024 15:04:05 +0000
Subject: [PATCH] ffmpeg: Support image2 demuxer

---
 ffmpeg/decoder.c    |  6 +++++-
 ffmpeg/ffmpeg.go    | 34 +++++++++++++++++++++++++++++++++-
 ffmpeg/transcoder.c | 10 ++++++++--
 ffmpeg/transcoder.h |  2 ++
 4 files changed, 48 insertions(+), 4 deletions(-)

diff --git a/ffmpeg/decoder.c b/ffmpeg/decoder.c
index 2c344ee17a..652c6f5120 100755
--- a/ffmpeg/decoder.c
+++ b/ffmpeg/decoder.c
@@ -338,8 +338,12 @@ int open_input(input_params *params, struct input_ctx *ctx)
   ctx->transmuxing = params->transmuxe;
 
   // open demuxer
-  ret = avformat_open_input(&ic, inp, NULL, NULL);
+  AVDictionary **demuxer_opts = NULL;
+  if (params->demuxer.opts) demuxer_opts = &params->demuxer.opts;
+  ret = avformat_open_input(&ic, inp, NULL, demuxer_opts);
   if (ret < 0) LPMS_ERR(open_input_err, "demuxer: Unable to open input");
+  // If avformat_open_input replaced the options AVDictionary with options that were not found free it
+  if (demuxer_opts) av_dict_free(demuxer_opts);
   ctx->ic = ic;
   ret = avformat_find_stream_info(ic, NULL);
   if (ret < 0) LPMS_ERR(open_input_err, "Unable to find input info");
diff --git a/ffmpeg/ffmpeg.go b/ffmpeg/ffmpeg.go
index de1c441b2b..407764d13d 100755
--- a/ffmpeg/ffmpeg.go
+++ b/ffmpeg/ffmpeg.go
@@ -97,6 +97,7 @@ type TranscodeOptionsIn struct {
 	Accel       Acceleration
 	Device      string
 	Transmuxing bool
+	Profile     VideoProfile
 }
 
 type TranscodeOptions struct {
@@ -649,6 +650,11 @@ func createCOutputParams(input *TranscodeOptionsIn, ps []TranscodeOptions) ([]C.
 			// needed for hw dec -> hw rescale -> sw enc
 			filters = filters + ",hwdownload,format=nv12"
 		}
+		if p.Accel == Nvidia && filepath.Ext(input.Fname) == ".png" {
+			// If the input is PNG image(s) and we are scaling on a Nvidia device
+			// we need to first convert to a pixel format that the scale_npp filter supports
+			filters = "format=nv12," + filters
+		}
 		// set FPS denominator to 1 if unset by user
 		if param.FramerateDen == 0 {
 			param.FramerateDen = 1
@@ -955,8 +961,34 @@ func (t *Transcoder) Transcode(input *TranscodeOptionsIn, ps []TranscodeOptions)
 	defer C.free(unsafe.Pointer(fname))
 	xcoderParams := C.CString("")
 	defer C.free(unsafe.Pointer(xcoderParams))
+
+	var demuxerOpts C.component_opts
+
+	ext := filepath.Ext(input.Fname)
+	// If the input has an image file extension setup the image2 demuxer
+	if ext == ".png" {
+		image2 := C.CString("image2")
+		defer C.free(unsafe.Pointer(image2))
+
+		demuxerOpts = C.component_opts{
+			name: image2,
+		}
+
+		if input.Profile.Framerate > 0 {
+			if input.Profile.FramerateDen == 0 {
+				input.Profile.FramerateDen = 1
+			}
+
+			// Do not try tofree in this function because in the C code avformat_open_input()
+			// will destroy this
+			demuxerOpts.opts = newAVOpts(map[string]string{
+				"framerate": fmt.Sprintf("%d/%d", input.Profile.Framerate, input.Profile.FramerateDen),
+			})
+		}
+	}
+
 	inp := &C.input_params{fname: fname, hw_type: hw_type, device: device, xcoderParams: xcoderParams,
-		handle: t.handle}
+		handle: t.handle, demuxer: demuxerOpts}
 	if input.Transmuxing {
 		inp.transmuxe = 1
 	}
diff --git a/ffmpeg/transcoder.c b/ffmpeg/transcoder.c
index 0247f5657e..00a1845bd1 100755
--- a/ffmpeg/transcoder.c
+++ b/ffmpeg/transcoder.c
@@ -160,17 +160,23 @@ int transcode_init(struct transcode_thread *h, input_params *inp,
 
   if (!inp) LPMS_ERR(transcode_cleanup, "Missing input params")
 
+  AVDictionary **demuxer_opts;
+  if (inp->demuxer.opts) demuxer_opts = &inp->demuxer.opts;
+
   // by default we re-use decoder between segments of same stream
   // unless we are using SW deocder and had to re-open IO or demuxer
   if (!ictx->ic) {
     // reopen demuxer for the input segment if needed
     // XXX could open_input() be re-used here?
-    ret = avformat_open_input(&ictx->ic, inp->fname, NULL, NULL);
+    ret = avformat_open_input(&ictx->ic, inp->fname, NULL, demuxer_opts);
     if (ret < 0) LPMS_ERR(transcode_cleanup, "Unable to reopen demuxer");
+    // If avformat_open_input replaced the options AVDictionary with options that were not found free it
+    if (demuxer_opts) av_dict_free(demuxer_opts);
     ret = avformat_find_stream_info(ictx->ic, NULL);
     if (ret < 0) LPMS_ERR(transcode_cleanup, "Unable to find info for reopened stream")
-  } else if (!ictx->ic->pb) {
+  } else if (is_mpegts(ictx->ic) && !ictx->ic->pb) {
     // reopen input segment file IO context if needed
+    // only necessary for mpegts
     ret = avio_open(&ictx->ic->pb, inp->fname, AVIO_FLAG_READ);
     if (ret < 0) LPMS_ERR(transcode_cleanup, "Unable to reopen file");
   } else reopen_decoders = 0;
diff --git a/ffmpeg/transcoder.h b/ffmpeg/transcoder.h
index 53ded33f35..3d9ff73ff2 100755
--- a/ffmpeg/transcoder.h
+++ b/ffmpeg/transcoder.h
@@ -51,6 +51,8 @@ typedef struct {
   char *device;
   char *xcoderParams;
 
+  // Optional demuxer opts
+  component_opts demuxer;
   // Optional video decoder + opts
   component_opts video;