video: rewrite filtering glue code

Get rid of the old vf.c code. Replace it with a generic filtering
framework, which can potentially handle more than just --vf. At least
reimplementing --af with this code is planned.

This changes some --vf semantics (including runtime behavior and the
"vf" command). The most important ones are listed in interface-changes.

vf_convert.c is renamed to f_swscale.c. It is now an internal filter
that can not be inserted by the user manually.

f_lavfi.c is a refactor of player/lavfi.c. The latter will be removed
once --lavfi-complex is reimplemented on top of f_lavfi.c. (which is
conceptually easy, but a big mess due to the data flow changes).

The existing filters are all changed heavily. The data flow of the new
filter framework is different. Especially EOF handling changes - EOF is
now a "frame" rather than a state, and must be passed through exactly
once.

Another major thing is that all filters must support dynamic format
changes. The filter reconfig() function goes away. (This sounds complex,
but since all filters need to handle EOF draining anyway, they can use
the same code, and it removes the mess with reconfig() having to predict
the output format, which completely breaks with libavfilter anyway.)

In addition, there is no automatic format negotiation or conversion.
libavfilter's primitive and insufficient API simply doesn't allow us to
do this in a reasonable way. Instead, filters can use f_autoconvert as
sub-filter, and tell it which formats they support. This filter will in
turn add actual conversion filters, such as f_swscale, to perform
necessary format changes.

vf_vapoursynth.c uses the same basic principle of operation as before,
but with worryingly different details in data flow. Still appears to
work.

The hardware deint filters (vf_vavpp.c, vf_d3d11vpp.c, vf_vdpaupp.c) are
heavily changed. Fortunately, they all used refqueue.c, which is for
sharing the data flow logic (especially for managing future/past
surfaces and such). It turns out it can be used to factor out most of
the data flow. Some of these filters accepted software input. Instead of
having ad-hoc upload code in each filter, surface upload is now
delegated to f_autoconvert, which can use f_hwupload to perform this.

Exporting VO capabilities is still a big mess (mp_stream_info stuff).

The D3D11 code drops the redundant image formats, and all code uses the
hw_subfmt (sw_format in FFmpeg) instead. Although that too seems to be a
big mess for now.

f_async_queue is unused.

1 files changed, 175 insertions, 0 deletions

diff --git a/filters/f_utils.c b/filters/f_utils.c
new file mode 100644
index 0000000000..f984a3b33a
--- /dev/null
+++ b/filters/f_utils.c
@@ -0,0 +1,175 @@
+#include "video/mp_image.h"
+
+#include "f_utils.h"
+#include "filter_internal.h"
+
+struct frame_duration_priv {
+    struct mp_image *buffered;
+};
+
+static void frame_duration_process(struct mp_filter *f)
+{
+    struct frame_duration_priv *p = f->priv;
+
+    if (!mp_pin_can_transfer_data(f->ppins[1], f->ppins[0]))
+        return;
+
+    struct mp_frame frame = mp_pin_out_read(f->ppins[0]);
+
+    if (frame.type == MP_FRAME_EOF && p->buffered) {
+        mp_pin_in_write(f->ppins[1], MAKE_FRAME(MP_FRAME_VIDEO, p->buffered));
+        p->buffered = NULL;
+        // Pass through the actual EOF in the next iteration.
+        mp_pin_out_repeat_eof(f->ppins[0]);
+    } else if (frame.type == MP_FRAME_VIDEO) {
+        struct mp_image *next = frame.data;
+        if (p->buffered) {
+            if (p->buffered->pts != MP_NOPTS_VALUE &&
+                next->pts != MP_NOPTS_VALUE &&
+                next->pts >= p->buffered->pts)
+                p->buffered->pkt_duration = next->pts - p->buffered->pts;
+            mp_pin_in_write(f->ppins[1], MAKE_FRAME(MP_FRAME_VIDEO, p->buffered));
+        } else {
+            mp_pin_out_request_data(f->ppins[0]);
+        }
+        p->buffered = next;
+    } else {
+        mp_pin_in_write(f->ppins[1], frame);
+    }
+}
+
+static void frame_duration_reset(struct mp_filter *f)
+{
+    struct frame_duration_priv *p = f->priv;
+
+    mp_image_unrefp(&p->buffered);
+}
+
+static const struct mp_filter_info frame_duration_filter = {
+    .name = "frame_duration",
+    .priv_size = sizeof(struct frame_duration_priv),
+    .process = frame_duration_process,
+    .reset = frame_duration_reset,
+};
+
+struct mp_filter *mp_compute_frame_duration_create(struct mp_filter *parent)
+{
+    struct mp_filter *f = mp_filter_create(parent, &frame_duration_filter);
+    if (!f)
+        return NULL;
+
+    mp_filter_add_pin(f, MP_PIN_IN, "in");
+    mp_filter_add_pin(f, MP_PIN_OUT, "out");
+
+    return f;
+}
+
+void mp_chain_filters(struct mp_pin *in, struct mp_pin *out,
+                      struct mp_filter **filters, int num_filters)
+{
+    for (int n = 0; n < num_filters; n++) {
+        if (!filters[n])
+            continue;
+        assert(filters[n]->num_pins == 2);
+        mp_pin_connect(filters[n]->pins[0], in);
+        in = filters[n]->pins[1];
+    }
+    mp_pin_connect(out, in);
+}
+
+// Make it repeat process().
+static void mark_progress(struct mp_subfilter *sub)
+{
+    // f == NULL is not really allowed, but at least don't crash.
+    struct mp_filter *f = mp_pin_get_manual_connection(sub->in);
+    if (f)
+        mp_filter_internal_mark_progress(f);
+}
+
+bool mp_subfilter_read(struct mp_subfilter *sub)
+{
+    if (sub->filter) {
+        if (mp_pin_can_transfer_data(sub->out, sub->filter->pins[1])) {
+            struct mp_frame frame = mp_pin_out_read(sub->filter->pins[1]);
+            if (sub->draining && frame.type == MP_FRAME_EOF) {
+                sub->draining = false;
+                TA_FREEP(&sub->filter);
+                mark_progress(sub);
+                return false;
+            }
+            mp_pin_in_write(sub->out, frame);
+            return false;
+        }
+        if (sub->draining)
+            return false;
+    }
+
+    struct mp_pin *out = sub->filter ? sub->filter->pins[0] : sub->out;
+
+    if (sub->frame.type)
+        return mp_pin_in_needs_data(out);
+
+    if (!mp_pin_can_transfer_data(out, sub->in))
+        return false;
+
+    sub->frame = mp_pin_out_read(sub->in);
+    return true;
+}
+
+void mp_subfilter_reset(struct mp_subfilter *sub)
+{
+    if (sub->filter && sub->draining)
+        TA_FREEP(&sub->filter);
+    sub->draining = false;
+    mp_frame_unref(&sub->frame);
+}
+
+void mp_subfilter_continue(struct mp_subfilter *sub)
+{
+    struct mp_pin *out = sub->filter ? sub->filter->pins[0] : sub->out;
+    // It was made sure earlier that the pin is writable, unless the filter
+    // was newly created, or a previously existing filter (which was going to
+    // accept input) was destroyed. In those cases, essentially restart
+    // data flow.
+    if (!mp_pin_in_needs_data(out)) {
+        mark_progress(sub);
+        return;
+    }
+    mp_pin_in_write(out, sub->frame);
+    sub->frame = MP_NO_FRAME;
+}
+
+void mp_subfilter_destroy(struct mp_subfilter *sub)
+{
+    TA_FREEP(&sub->filter);
+    sub->draining = false;
+}
+
+bool mp_subfilter_drain_destroy(struct mp_subfilter *sub)
+{
+    if (!sub->draining && sub->filter) {
+        // We know the filter is writable (unless the user created a new filter
+        // and immediately called this function, which is invalid).
+        mp_pin_in_write(sub->filter->pins[0], MP_EOF_FRAME);
+        sub->draining = true;
+    }
+    return !sub->filter;
+}
+
+static const struct mp_filter_info bidir_nop_filter = {
+    .name = "nop",
+};
+
+struct mp_filter *mp_bidir_nop_filter_create(struct mp_filter *parent)
+{
+    struct mp_filter *f = mp_filter_create(parent, &bidir_nop_filter);
+    if (!f)
+        return NULL;
+
+    mp_filter_add_pin(f, MP_PIN_IN, "in");
+    mp_filter_add_pin(f, MP_PIN_OUT, "out");
+
+    mp_pin_connect(f->ppins[1], f->ppins[0]);
+
+    return f;
+}