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, 299 insertions, 0 deletions

diff --git a/filters/f_hwtransfer.c b/filters/f_hwtransfer.c
new file mode 100644
index 0000000000..6ffda567ae
--- /dev/null
+++ b/filters/f_hwtransfer.c
@@ -0,0 +1,299 @@
+#include <libavutil/buffer.h>
+#include <libavutil/hwcontext.h>
+#include <libavutil/mem.h>
+
+#include "video/fmt-conversion.h"
+#include "video/hwdec.h"
+#include "video/mp_image.h"
+#include "video/mp_image_pool.h"
+
+#include "f_hwtransfer.h"
+#include "filter_internal.h"
+
+struct priv {
+    AVBufferRef *av_device_ctx;
+
+    AVBufferRef *hw_pool;
+
+    int last_input_fmt;
+    int last_upload_fmt;
+    int last_sw_fmt;
+
+    struct mp_hwupload public;
+};
+
+static bool update_format_decision(struct priv *p, int input_fmt)
+{
+    struct mp_hwupload *u = &p->public;
+
+    if (!input_fmt)
+        return false;
+
+    if (input_fmt == p->last_input_fmt)
+        return true;
+
+    p->last_input_fmt = 0;
+
+    int res = mp_imgfmt_select_best_list(u->upload_fmts, u->num_upload_fmts,
+                                         input_fmt);
+
+    if (!res)
+        return false;
+
+    // Find which sw format we should use.
+    // NOTE: if there are ever any hw APIs that actually do expensive
+    // conversions on mismatching format uploads, we should probably first look
+    // which sw format is preferred?
+    int index = -1;
+    for (int n = 0; n < u->num_upload_fmts; n++) {
+        if (u->upload_fmts[n] == res)
+            index = n;
+    }
+
+    if (index < 0)
+        return false;
+
+    for (int n = 0; n < u->num_fmts; n++) {
+        if (u->fmt_upload_index[n] >= index &&
+            index  < u->fmt_upload_index[n] + u->fmt_upload_num[n])
+        {
+            p->last_input_fmt = input_fmt;
+            p->last_upload_fmt = u->upload_fmts[index];
+            p->last_sw_fmt = u->fmts[n];
+            MP_INFO(u->f, "upload %s -> %s\n",
+                    mp_imgfmt_to_name(p->last_sw_fmt),
+                    mp_imgfmt_to_name(p->last_input_fmt));
+            return true;
+        }
+    }
+
+    return false;
+}
+
+int mp_hwupload_find_upload_format(struct mp_hwupload *u, int imgfmt)
+{
+    struct priv *p = u->f->priv;
+
+    if (!update_format_decision(p, imgfmt))
+        return 0;
+    return p->last_upload_fmt;
+}
+
+static void process(struct mp_filter *f)
+{
+    struct 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 (mp_frame_is_signaling(frame)) {
+        mp_pin_in_write(f->ppins[1], frame);
+        return;
+    }
+    if (frame.type != MP_FRAME_VIDEO) {
+        MP_ERR(f, "unsupported frame type\n");
+        goto error;
+    }
+    struct mp_image *src = frame.data;
+
+    // As documented, just pass though HW frames.
+    if (IMGFMT_IS_HWACCEL(src->imgfmt)) {
+        mp_pin_in_write(f->ppins[1], frame);
+        return;
+    }
+
+    if (src->w % 2 || src->h % 2) {
+        MP_ERR(f, "non-mod 2 input frames unsupported\n");
+        goto error;
+    }
+
+    if (!update_format_decision(p, src->imgfmt)) {
+        MP_ERR(f, "no hw upload format found\n");
+        goto error;
+    }
+
+    if (!mp_update_av_hw_frames_pool(&p->hw_pool, p->av_device_ctx,
+                                     p->public.hw_imgfmt, p->last_sw_fmt,
+                                     src->w, src->h))
+    {
+        MP_ERR(f, "failed to create frame pool\n");
+        goto error;
+    }
+
+    struct mp_image *dst = mp_av_pool_image_hw_upload(p->hw_pool, src);
+    if (!dst)
+        goto error;
+
+    mp_frame_unref(&frame);
+    mp_pin_in_write(f->ppins[1], MAKE_FRAME(MP_FRAME_VIDEO, dst));
+
+    return;
+
+error:
+    mp_frame_unref(&frame);
+    MP_ERR(f, "failed to upload frame\n");
+    mp_filter_internal_mark_failed(f);
+}
+
+static void destroy(struct mp_filter *f)
+{
+    struct priv *p = f->priv;
+
+    av_buffer_unref(&p->hw_pool);
+    av_buffer_unref(&p->av_device_ctx);
+}
+
+static const struct mp_filter_info hwupload_filter = {
+    .name = "hwupload",
+    .priv_size = sizeof(struct priv),
+    .process = process,
+    .destroy = destroy,
+};
+
+// The VO layer might have restricted format support. It might actually
+// work if this is input to a conversion filter anyway, but our format
+// negotiation is too stupid and non-existent to detect this.
+// So filter out all not explicitly supported formats.
+static bool vo_supports(struct mp_hwdec_ctx *ctx, int hw_fmt, int sw_fmt)
+{
+    if (!ctx->hw_imgfmt)
+        return true; // if unset, all formats are allowed
+    if (ctx->hw_imgfmt != hw_fmt)
+        return false;
+
+    for (int i = 0; ctx->supported_formats &&  ctx->supported_formats[i]; i++) {
+        if (ctx->supported_formats[i] == sw_fmt)
+            return true;
+    }
+
+    return false;
+}
+
+static bool probe_formats(struct mp_hwupload *u, int hw_imgfmt)
+{
+    struct priv *p = u->f->priv;
+
+    u->hw_imgfmt = hw_imgfmt;
+    u->num_fmts = 0;
+    u->num_upload_fmts = 0;
+
+    struct mp_stream_info *info = mp_filter_find_stream_info(u->f);
+    if (!info || !info->hwdec_devs) {
+        MP_ERR(u->f, "no hw context\n");
+        return false;
+    }
+
+    struct mp_hwdec_ctx *ctx = NULL;
+    AVHWFramesConstraints *cstr = NULL;
+
+    for (int n = 0; ; n++) {
+        struct mp_hwdec_ctx *cur = hwdec_devices_get_n(info->hwdec_devs, n);
+        if (!cur)
+            break;
+        if (!cur->av_device_ref)
+            continue;
+        cstr = av_hwdevice_get_hwframe_constraints(cur->av_device_ref, NULL);
+        if (!cstr)
+            continue;
+        bool found = false;
+        for (int i = 0; cstr->valid_hw_formats &&
+                        cstr->valid_hw_formats[i] != AV_PIX_FMT_NONE; i++)
+        {
+            found |= cstr->valid_hw_formats[i] == imgfmt2pixfmt(hw_imgfmt);
+        }
+        if (found && (!cur->hw_imgfmt || cur->hw_imgfmt == hw_imgfmt)) {
+            ctx = cur;
+            break;
+        }
+        av_hwframe_constraints_free(&cstr);
+    }
+
+    if (!ctx) {
+        MP_ERR(u->f, "no support for this hw format\n");
+        return false;
+    }
+
+    // Probe for supported formats. This is very roundabout, because the
+    // hwcontext API does not give us this information directly. We resort to
+    // creating temporary AVHWFramesContexts in order to retrieve the list of
+    // supported formats. This should be relatively cheap as we don't create
+    // any real frames (although some backends do for probing info).
+
+    for (int n = 0; cstr->valid_sw_formats &&
+                    cstr->valid_sw_formats[n] != AV_PIX_FMT_NONE; n++)
+    {
+        int imgfmt = pixfmt2imgfmt(cstr->valid_sw_formats[n]);
+        if (!imgfmt)
+            continue;
+
+        MP_VERBOSE(u->f, "looking at format %s\n", mp_imgfmt_to_name(imgfmt));
+
+        // Creates an AVHWFramesContexts with the given parameters.
+        AVBufferRef *frames = NULL;
+        if (!mp_update_av_hw_frames_pool(&frames, ctx->av_device_ref,
+                                        hw_imgfmt, imgfmt, 128, 128))
+        {
+            MP_WARN(u->f, "failed to allocate pool\n");
+            continue;
+        }
+
+        enum AVPixelFormat *fmts;
+        if (av_hwframe_transfer_get_formats(frames,
+                            AV_HWFRAME_TRANSFER_DIRECTION_TO, &fmts, 0) >= 0)
+        {
+            int index = u->num_fmts;
+            MP_TARRAY_APPEND(p, u->fmts, u->num_fmts, imgfmt);
+            MP_TARRAY_GROW(p, u->fmt_upload_index, index);
+            MP_TARRAY_GROW(p, u->fmt_upload_num, index);
+
+            u->fmt_upload_index[index] = u->num_upload_fmts;
+
+            for (int i = 0; fmts[i] != AV_PIX_FMT_NONE; i++) {
+                int fmt = pixfmt2imgfmt(fmts[i]);
+                if (!fmt)
+                    continue;
+                MP_VERBOSE(u->f, "supports %s\n", mp_imgfmt_to_name(fmt));
+                if (vo_supports(ctx, hw_imgfmt, fmt))
+                    MP_TARRAY_APPEND(p, u->upload_fmts, u->num_upload_fmts, fmt);
+            }
+
+            u->fmt_upload_num[index] =
+                u->num_upload_fmts - u->fmt_upload_index[index];
+
+            av_free(fmts);
+        }
+
+        av_buffer_unref(&frames);
+    }
+
+    p->av_device_ctx = av_buffer_ref(ctx->av_device_ref);
+    if (!p->av_device_ctx)
+        return false;
+
+    return u->num_upload_fmts > 0;
+}
+
+struct mp_hwupload *mp_hwupload_create(struct mp_filter *parent, int hw_imgfmt)
+{
+    struct mp_filter *f = mp_filter_create(parent, &hwupload_filter);
+    if (!f)
+        return NULL;
+
+    struct priv *p = f->priv;
+    struct mp_hwupload *u = &p->public;
+    u->f = f;
+
+    mp_filter_add_pin(f, MP_PIN_IN, "in");
+    mp_filter_add_pin(f, MP_PIN_OUT, "out");
+
+    if (!probe_formats(u, hw_imgfmt)) {
+        MP_ERR(f, "hardware format not supported\n");
+        goto error;
+    }
+
+    return u;
+error:
+    talloc_free(f);
+    return NULL;
+}