From ff115d70615e40948299e4221c58047570599486 Mon Sep 17 00:00:00 2001
From: Denis Pauk <pauk.denis@gmail.com>
Date: Sat, 7 Sep 2024 16:25:33 +0300
Subject: [PATCH] client: update mpeg video decoder

https://github.com/phoboslab/pl_mpeg/blob/3198122a19c1685f041d0b6ef7dd2918a4959352/pl_mpeg.h
---
 src/client/cinema/pl_mpeg.h | 46 +++++++++++++++++++++++++++++++++----
 1 file changed, 41 insertions(+), 5 deletions(-)

diff --git a/src/client/cinema/pl_mpeg.h b/src/client/cinema/pl_mpeg.h
index 8b56a1f2..50cc9b21 100644
--- a/src/client/cinema/pl_mpeg.h
+++ b/src/client/cinema/pl_mpeg.h
@@ -346,6 +346,7 @@ int plm_get_num_video_streams(plm_t *self);
 
 int plm_get_width(plm_t *self);
 int plm_get_height(plm_t *self);
+double plm_get_pixel_aspect_ratio(plm_t *self);
 
 
 // Get the framerate of the video stream in frames per second.
@@ -583,7 +584,7 @@ static const int PLM_DEMUX_PACKET_PRIVATE = 0xBD;
 static const int PLM_DEMUX_PACKET_AUDIO_1 = 0xC0;
 static const int PLM_DEMUX_PACKET_AUDIO_2 = 0xC1;
 static const int PLM_DEMUX_PACKET_AUDIO_3 = 0xC2;
-static const int PLM_DEMUX_PACKET_AUDIO_4 = 0xC2;
+static const int PLM_DEMUX_PACKET_AUDIO_4 = 0xC3;
 static const int PLM_DEMUX_PACKET_VIDEO_1 = 0xE0;
 
 
@@ -685,6 +686,7 @@ int plm_video_has_header(plm_video_t *self);
 // Get the framerate in frames per second.
 
 double plm_video_get_framerate(plm_video_t *self);
+double plm_video_get_pixel_aspect_ratio(plm_video_t *self);
 
 
 // Get the display width/height.
@@ -1044,6 +1046,12 @@ double plm_get_framerate(plm_t *self) {
 		: 0;
 }
 
+double plm_get_pixel_aspect_ratio(plm_t *self) {
+	return (plm_init_decoders(self) && self->video_decoder)
+		? plm_video_get_pixel_aspect_ratio(self->video_decoder)
+		: 0;
+}
+
 int plm_get_num_audio_streams(plm_t *self) {
 	return plm_demux_get_num_audio_streams(self->demux);
 }
@@ -2227,6 +2235,14 @@ static const int PLM_START_USER_DATA = 0xB2;
 #define PLM_START_IS_SLICE(c) \
 	(c >= PLM_START_SLICE_FIRST && c <= PLM_START_SLICE_LAST)
 
+static const float PLM_VIDEO_PIXEL_ASPECT_RATIO[] = {
+	1.0000, /* square pixels */
+	0.6735, /* 3:4? */
+	0.7031, /* MPEG-1 / MPEG-2 video encoding divergence? */
+	0.7615, 0.8055, 0.8437, 0.8935, 0.9157, 0.9815,
+	1.0255, 1.0695, 1.0950, 1.1575, 1.2051,
+};
+
 static const double PLM_VIDEO_PICTURE_RATE[] = {
 	0.000, 23.976, 24.000, 25.000, 29.970, 30.000, 50.000, 59.940,
 	60.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000
@@ -2620,6 +2636,7 @@ typedef struct {
 
 struct plm_video_t {
 	double framerate;
+	double pixel_aspect_ratio;
 	double time;
 	int frames_decoded;
 	int width;
@@ -2728,6 +2745,12 @@ double plm_video_get_framerate(plm_video_t *self) {
 		: 0;
 }
 
+double plm_video_get_pixel_aspect_ratio(plm_video_t *self) {
+	return plm_video_has_header(self)
+		? self->pixel_aspect_ratio
+		: 0;
+}
+
 int plm_video_get_width(plm_video_t *self) {
 	return plm_video_has_header(self)
 		? self->width
@@ -2863,9 +2886,22 @@ int plm_video_decode_sequence_header(plm_video_t *self) {
 		return FALSE;
 	}
 
-	// Skip pixel aspect ratio
-	plm_buffer_skip(self->buffer, 4);
+	// Get pixel aspect ratio
+	int pixel_aspect_ratio_code;
+	pixel_aspect_ratio_code = plm_buffer_read(self->buffer, 4);
+	pixel_aspect_ratio_code -= 1;
+	if (pixel_aspect_ratio_code < 0) {
+		pixel_aspect_ratio_code = 0;
+	}
+	int par_last = (sizeof(PLM_VIDEO_PIXEL_ASPECT_RATIO) /
+			sizeof(PLM_VIDEO_PIXEL_ASPECT_RATIO[0]) - 1);
+	if (pixel_aspect_ratio_code > par_last) {
+		pixel_aspect_ratio_code = par_last;
+	}
+	self->pixel_aspect_ratio =
+		PLM_VIDEO_PIXEL_ASPECT_RATIO[pixel_aspect_ratio_code];
 
+	// Get frame rate
 	self->framerate = PLM_VIDEO_PICTURE_RATE[plm_buffer_read(self->buffer, 4)];
 
 	// Skip bit_rate, marker, buffer_size and constrained bit
@@ -3176,7 +3212,7 @@ int plm_video_decode_motion_vector(plm_video_t *self, int r_size, int motion) {
 	if (motion > (fscale << 4) - 1) {
 		motion -= fscale << 5;
 	}
-	else if (motion < ((-fscale) << 4)) {
+	else if (motion < (int)((unsigned)(-fscale) << 4)) {
 		motion += fscale << 5;
 	}
 
@@ -3364,7 +3400,7 @@ void plm_video_decode_block(plm_video_t *self, int block) {
 		n++;
 
 		// Dequantize, oddify, clip
-		level <<= 1;
+		level = (unsigned)level << 1;
 		if (!self->macroblock_intra) {
 			level += (level < 0 ? -1 : 1);
 		}