fftools/ffmpeg_filter: refactor setting input timebase

Treat it analogously to stream parameters like format/dimensions/etc.
This is functionally different from previous code in 2 ways:
* for non-CFR video, the frame timebase (set by the decoder) is used
  rather than the demuxer timebase
* for sub2video, AV_TIME_BASE_Q is used, which is hardcoded by the
  subtitle decoding API

These changes should avoid unnecessary and potentially lossy timestamp
conversions from decoder timebase into the demuxer one.

Changes the timebases used in sub2video tests.

3 files changed, 106 insertions, 101 deletions

diff --git a/fftools/ffmpeg_filter.c b/fftools/ffmpeg_filter.c
index 7d5b3a0e9d..da6687028a 100644
--- a/fftools/ffmpeg_filter.c
+++ b/fftools/ffmpeg_filter.c
@@ -148,6 +148,8 @@ typedef struct InputFilterPriv {
 
     // fallback parameters to use when no input is ever sent
     struct {
+        AVRational          time_base;
+
         int                 format;
 
         int                 width;
@@ -696,6 +698,8 @@ static int ifilter_bind_ist(InputFilter *ifilter, InputStream *ist)
            palettes for all rectangles are identical or compatible */
         ifp->format = AV_PIX_FMT_RGB32;
 
+        ifp->time_base = AV_TIME_BASE_Q;
+
         av_log(fgp, AV_LOG_VERBOSE, "sub2video: using %dx%d canvas\n",
                ifp->width, ifp->height);
     }
@@ -1469,7 +1473,6 @@ static int configure_input_video_filter(FilterGraph *fg, AVFilterGraph *graph,
     AVFilterContext *last_filter;
     const AVFilter *buffer_filt = avfilter_get_by_name("buffer");
     const AVPixFmtDescriptor *desc;
-    InputStream *ist = ifp->ist;
     AVRational fr = ifp->opts.framerate;
     AVRational sar;
     AVBPrint args;
@@ -1482,9 +1485,6 @@ static int configure_input_video_filter(FilterGraph *fg, AVFilterGraph *graph,
     if (ifp->type_src == AVMEDIA_TYPE_SUBTITLE)
         sub2video_prepare(ifp);
 
-    ifp->time_base = (ifp->opts.flags & IFILTER_FLAG_CFR) ?
-                     av_inv_q(ifp->opts.framerate) : ist->st->time_base;
-
     sar = ifp->sample_aspect_ratio;
     if(!sar.den)
         sar = (AVRational){0,1};
@@ -1575,8 +1575,6 @@ static int configure_input_audio_filter(FilterGraph *fg, AVFilterGraph *graph,
     char name[255];
     int ret, pad_idx = 0;
 
-    ifp->time_base = (AVRational){ 1, ifp->sample_rate };
-
     av_bprint_init(&args, 0, AV_BPRINT_SIZE_AUTOMATIC);
     av_bprintf(&args, "time_base=%d/%d:sample_rate=%d:sample_fmt=%s",
                ifp->time_base.num, ifp->time_base.den,
@@ -1804,6 +1802,8 @@ int ifilter_parameters_from_dec(InputFilter *ifilter, const AVCodecContext *dec)
 {
     InputFilterPriv *ifp = ifp_from_ifilter(ifilter);
 
+    ifp->fallback.time_base = dec->pkt_timebase;
+
     if (dec->codec_type == AVMEDIA_TYPE_VIDEO) {
         ifp->fallback.format                 = dec->pix_fmt;
         ifp->fallback.width                  = dec->width;
@@ -1835,6 +1835,10 @@ static int ifilter_parameters_from_frame(InputFilter *ifilter, const AVFrame *fr
     if (ret < 0)
         return ret;
 
+    ifp->time_base = (ifp->type == AVMEDIA_TYPE_AUDIO)    ? (AVRational){ 1, frame->sample_rate } :
+                     (ifp->opts.flags & IFILTER_FLAG_CFR) ? av_inv_q(ifp->opts.framerate)         :
+                     frame->time_base;
+
     ifp->format              = frame->format;
 
     ifp->width               = frame->width;
@@ -2523,6 +2527,7 @@ static int send_eof(FilterGraphThread *fgt, InputFilter *ifilter,
             ifp->sample_aspect_ratio    = ifp->fallback.sample_aspect_ratio;
             ifp->color_space            = ifp->fallback.color_space;
             ifp->color_range            = ifp->fallback.color_range;
+            ifp->time_base              = ifp->fallback.time_base;
 
             ret = av_channel_layout_copy(&ifp->ch_layout,
                                          &ifp->fallback.ch_layout);
diff --git a/tests/ref/fate/sub2video_basic b/tests/ref/fate/sub2video_basic
index a6eb1a34ea..2e4dcb625e 100644
--- a/tests/ref/fate/sub2video_basic
+++ b/tests/ref/fate/sub2video_basic
@@ -1,95 +1,95 @@
-#tb 0: 1/1000
+#tb 0: 1/1000000
 #media_type 0: video
 #codec_id 0: rawvideo
 #dimensions 0: 720x480
 #sar 0: 0/1
-0,     132499,     132499,        0,  1382400, 0x00000000
-0,     132499,     132499,        0,  1382400, 0x8c93c2ba
-0,     137459,     137459,        0,  1382400, 0x00000000
-0,     147355,     147355,        0,  1382400, 0xb02e32ca
-0,     152088,     152088,        0,  1382400, 0x00000000
-0,     180797,     180797,        0,  1382400, 0x83b71116
-0,     183357,     183357,        0,  1382400, 0x00000000
-0,     183433,     183433,        0,  1382400, 0x85547fd1
-0,     185799,     185799,        0,  1382400, 0x00000000
-0,     185909,     185909,        0,  1382400, 0x00000000
-0,     185910,     185910,        0,  1382400, 0xb6a8f181
-0,     188606,     188606,        0,  1382400, 0x00000000
-0,     188663,     188663,        0,  1382400, 0xb64d1a2c
-0,     189925,     189925,        0,  1382400, 0x00000000
-0,     190014,     190014,        0,  1382400, 0x7b37ecf3
-0,     191675,     191675,        0,  1382400, 0x00000000
-0,     199724,     199724,        0,  1382400, 0xdc025bd1
-0,     201089,     201089,        0,  1382400, 0x00000000
-0,     201175,     201175,        0,  1382400, 0x688b294d
-0,     202733,     202733,        0,  1382400, 0x00000000
-0,     202819,     202819,        0,  1382400, 0xa2b33d1b
-0,     204684,     204684,        0,  1382400, 0x00000000
-0,     204762,     204762,        0,  1382400, 0xb3e525e3
-0,     206730,     206730,        0,  1382400, 0x00000000
-0,     206806,     206806,        0,  1382400, 0xaa8fbdd7
-0,     208637,     208637,        0,  1382400, 0x00000000
-0,     208716,     208716,        0,  1382400, 0x7b7f26dd
-0,     209978,     209978,        0,  1382400, 0x00000000
-0,     210051,     210051,        0,  1382400, 0x15e2f836
-0,     211575,     211575,        0,  1382400, 0x00000000
-0,     211644,     211644,        0,  1382400, 0x0fee9b0c
-0,     214306,     214306,        0,  1382400, 0x00000000
-0,     214380,     214380,        0,  1382400, 0x89d62791
-0,     217144,     217144,        0,  1382400, 0x00000000
-0,     217225,     217225,        0,  1382400, 0xa6a9fd74
-0,     219591,     219591,        0,  1382400, 0x00000000
-0,     219652,     219652,        0,  1382400, 0x7896178d
-0,     221483,     221483,        0,  1382400, 0x00000000
-0,     223531,     223531,        0,  1382400, 0x01751a52
-0,     225863,     225863,        0,  1382400, 0x00000000
-0,     227510,     227510,        0,  1382400, 0xa3959c6f
-0,     230809,     230809,        0,  1382400, 0x00000000
-0,     230872,     230872,        0,  1382400, 0x3d3ea47b
-0,     233033,     233033,        0,  1382400, 0x00000000
-0,     233124,     233124,        0,  1382400, 0x593f8b24
-0,     237220,     237220,        0,  1382400, 0x00000000
-0,     237303,     237303,        0,  1382400, 0x171f05ba
-0,     240033,     240033,        0,  1382400, 0x00000000
-0,     240106,     240106,        0,  1382400, 0xb014cdf1
-0,     242165,     242165,        0,  1382400, 0x00000000
-0,     273556,     273556,        0,  1382400, 0xd918e667
-0,     275217,     275217,        0,  1382400, 0x00000000
-0,     295445,     295445,        0,  1382400, 0xc9406331
-0,     296776,     296776,        0,  1382400, 0x00000000
-0,     300049,     300049,        0,  1382400, 0xaf08b10d
-0,     301949,     301949,        0,  1382400, 0x00000000
-0,     302034,     302034,        0,  1382400, 0x00000000
-0,     302035,     302035,        0,  1382400, 0x853a9d93
-0,     303559,     303559,        0,  1382400, 0x00000000
-0,     304203,     304203,        0,  1382400, 0x7491a87d
-0,     305898,     305898,        0,  1382400, 0x00000000
-0,     305947,     305947,        0,  1382400, 0xf7383c58
-0,     307881,     307881,        0,  1382400, 0x00000000
-0,     307957,     307957,        0,  1382400, 0xe66be411
-0,     309720,     309720,        0,  1382400, 0x00000000
-0,     321295,     321295,        0,  1382400, 0xd6850362
-0,     323263,     323263,        0,  1382400, 0x00000000
-0,     323356,     323356,        0,  1382400, 0x3e1ed109
-0,     324584,     324584,        0,  1382400, 0x00000000
-0,     324640,     324640,        0,  1382400, 0x39c1b7bd
-0,     326403,     326403,        0,  1382400, 0x00000000
-0,     327193,     327193,        0,  1382400, 0x35b85f2e
-0,     328285,     328285,        0,  1382400, 0x00000000
-0,     328360,     328360,        0,  1382400, 0x00000000
-0,     328361,     328361,        0,  1382400, 0x83f103e5
-0,     329885,     329885,        0,  1382400, 0x00000000
-0,     329946,     329946,        0,  1382400, 0xbc1ca9b3
-0,     331106,     331106,        0,  1382400, 0x00000000
-0,     331230,     331230,        0,  1382400, 0x94d4a51e
-0,     332857,     332857,        0,  1382400, 0x00000000
-0,     332924,     332924,        0,  1382400, 0xf88cdfde
-0,     334687,     334687,        0,  1382400, 0x00000000
-0,     342600,     342600,        0,  1382400, 0xdd51423b
-0,     344431,     344431,        0,  1382400, 0x00000000
-0,     346771,     346771,        0,  1382400, 0x08259fa4
-0,     348329,     348329,        0,  1382400, 0x00000000
-0,     357640,     357640,        0,  1382400, 0x1663fa34
-0,     359767,     359767,        0,  1382400, 0x00000000
-0,     359834,     359834,        0,  1382400, 0xda2ceb55
-0,     361096,     361096,        0,  1382400, 0x00000000
+0,  132499000,  132499000,        0,  1382400, 0x00000000
+0,  132499000,  132499000,        0,  1382400, 0x8c93c2ba
+0,  137459000,  137459000,        0,  1382400, 0x00000000
+0,  147355000,  147355000,        0,  1382400, 0xb02e32ca
+0,  152088000,  152088000,        0,  1382400, 0x00000000
+0,  180797000,  180797000,        0,  1382400, 0x83b71116
+0,  183357000,  183357000,        0,  1382400, 0x00000000
+0,  183433000,  183433000,        0,  1382400, 0x85547fd1
+0,  185799000,  185799000,        0,  1382400, 0x00000000
+0,  185909999,  185909999,        0,  1382400, 0x00000000
+0,  185910000,  185910000,        0,  1382400, 0xb6a8f181
+0,  188606000,  188606000,        0,  1382400, 0x00000000
+0,  188663000,  188663000,        0,  1382400, 0xb64d1a2c
+0,  189925000,  189925000,        0,  1382400, 0x00000000
+0,  190014000,  190014000,        0,  1382400, 0x7b37ecf3
+0,  191675000,  191675000,        0,  1382400, 0x00000000
+0,  199724000,  199724000,        0,  1382400, 0xdc025bd1
+0,  201089000,  201089000,        0,  1382400, 0x00000000
+0,  201175000,  201175000,        0,  1382400, 0x688b294d
+0,  202733000,  202733000,        0,  1382400, 0x00000000
+0,  202819000,  202819000,        0,  1382400, 0xa2b33d1b
+0,  204684000,  204684000,        0,  1382400, 0x00000000
+0,  204762000,  204762000,        0,  1382400, 0xb3e525e3
+0,  206730000,  206730000,        0,  1382400, 0x00000000
+0,  206806000,  206806000,        0,  1382400, 0xaa8fbdd7
+0,  208637000,  208637000,        0,  1382400, 0x00000000
+0,  208716000,  208716000,        0,  1382400, 0x7b7f26dd
+0,  209978000,  209978000,        0,  1382400, 0x00000000
+0,  210051000,  210051000,        0,  1382400, 0x15e2f836
+0,  211575000,  211575000,        0,  1382400, 0x00000000
+0,  211644000,  211644000,        0,  1382400, 0x0fee9b0c
+0,  214306000,  214306000,        0,  1382400, 0x00000000
+0,  214380000,  214380000,        0,  1382400, 0x89d62791
+0,  217144000,  217144000,        0,  1382400, 0x00000000
+0,  217225000,  217225000,        0,  1382400, 0xa6a9fd74
+0,  219591000,  219591000,        0,  1382400, 0x00000000
+0,  219652000,  219652000,        0,  1382400, 0x7896178d
+0,  221483000,  221483000,        0,  1382400, 0x00000000
+0,  223531000,  223531000,        0,  1382400, 0x01751a52
+0,  225863000,  225863000,        0,  1382400, 0x00000000
+0,  227510000,  227510000,        0,  1382400, 0xa3959c6f
+0,  230809000,  230809000,        0,  1382400, 0x00000000
+0,  230872000,  230872000,        0,  1382400, 0x3d3ea47b
+0,  233033000,  233033000,        0,  1382400, 0x00000000
+0,  233124000,  233124000,        0,  1382400, 0x593f8b24
+0,  237220000,  237220000,        0,  1382400, 0x00000000
+0,  237303000,  237303000,        0,  1382400, 0x171f05ba
+0,  240033000,  240033000,        0,  1382400, 0x00000000
+0,  240106000,  240106000,        0,  1382400, 0xb014cdf1
+0,  242165000,  242165000,        0,  1382400, 0x00000000
+0,  273556000,  273556000,        0,  1382400, 0xd918e667
+0,  275217000,  275217000,        0,  1382400, 0x00000000
+0,  295445000,  295445000,        0,  1382400, 0xc9406331
+0,  296776000,  296776000,        0,  1382400, 0x00000000
+0,  300049000,  300049000,        0,  1382400, 0xaf08b10d
+0,  301949000,  301949000,        0,  1382400, 0x00000000
+0,  302034999,  302034999,        0,  1382400, 0x00000000
+0,  302035000,  302035000,        0,  1382400, 0x853a9d93
+0,  303559000,  303559000,        0,  1382400, 0x00000000
+0,  304203000,  304203000,        0,  1382400, 0x7491a87d
+0,  305898000,  305898000,        0,  1382400, 0x00000000
+0,  305947000,  305947000,        0,  1382400, 0xf7383c58
+0,  307881000,  307881000,        0,  1382400, 0x00000000
+0,  307957000,  307957000,        0,  1382400, 0xe66be411
+0,  309720000,  309720000,        0,  1382400, 0x00000000
+0,  321295000,  321295000,        0,  1382400, 0xd6850362
+0,  323263000,  323263000,        0,  1382400, 0x00000000
+0,  323356000,  323356000,        0,  1382400, 0x3e1ed109
+0,  324584000,  324584000,        0,  1382400, 0x00000000
+0,  324640000,  324640000,        0,  1382400, 0x39c1b7bd
+0,  326403000,  326403000,        0,  1382400, 0x00000000
+0,  327193000,  327193000,        0,  1382400, 0x35b85f2e
+0,  328285000,  328285000,        0,  1382400, 0x00000000
+0,  328360999,  328360999,        0,  1382400, 0x00000000
+0,  328361000,  328361000,        0,  1382400, 0x83f103e5
+0,  329885000,  329885000,        0,  1382400, 0x00000000
+0,  329946000,  329946000,        0,  1382400, 0xbc1ca9b3
+0,  331106000,  331106000,        0,  1382400, 0x00000000
+0,  331230000,  331230000,        0,  1382400, 0x94d4a51e
+0,  332857000,  332857000,        0,  1382400, 0x00000000
+0,  332924000,  332924000,        0,  1382400, 0xf88cdfde
+0,  334687000,  334687000,        0,  1382400, 0x00000000
+0,  342600000,  342600000,        0,  1382400, 0xdd51423b
+0,  344431000,  344431000,        0,  1382400, 0x00000000
+0,  346771000,  346771000,        0,  1382400, 0x08259fa4
+0,  348329000,  348329000,        0,  1382400, 0x00000000
+0,  357640000,  357640000,        0,  1382400, 0x1663fa34
+0,  359767000,  359767000,        0,  1382400, 0x00000000
+0,  359834000,  359834000,        0,  1382400, 0xda2ceb55
+0,  361096000,  361096000,        0,  1382400, 0x00000000
diff --git a/tests/ref/fate/sub2video_time_limited b/tests/ref/fate/sub2video_time_limited
index c7d48d639f..07d50fc697 100644
--- a/tests/ref/fate/sub2video_time_limited
+++ b/tests/ref/fate/sub2video_time_limited
@@ -1,8 +1,8 @@
-#tb 0: 1/90000
+#tb 0: 1/1000000
 #media_type 0: video
 #codec_id 0: rawvideo
 #dimensions 0: 1920x1080
 #sar 0: 0/1
-0,       6072,       6072,        0,  8294400, 0x00000000
-0,       6072,       6072,        0,  8294400, 0xa87c518f
-0,      36101,      36101,        0,  8294400, 0xa87c518f
+0,      67467,      67467,        0,  8294400, 0x00000000
+0,      67467,      67467,        0,  8294400, 0xa87c518f
+0,     401132,     401132,        0,  8294400, 0xa87c518f