video-dsp-src.c

Video source using Stream.

/* PipeWire */
/* SPDX-FileCopyrightText: Copyright © 2018 Wim Taymans */
/* SPDX-FileCopyrightText: Copyright © 2023 Columbarius */
/* SPDX-License-Identifier: MIT */
 
/*
 [title]
 Video source using \ref pw_stream.
 [title]
 */
 
#include <stdio.h>
#include <errno.h>
#include <signal.h>
#include <math.h>
 
#include <spa/param/video/format-utils.h>
#include <spa/param/tag-utils.h>
#include <spa/debug/pod.h>
 
#include <pipewire/pipewire.h>
 
#define BPP             16
#define CURSOR_WIDTH    64
#define CURSOR_HEIGHT   64
#define CURSOR_BPP      4
 
#define MAX_BUFFERS     64
 
#define M_PI_M2 ( M_PI + M_PI )
 
struct pixel {
        float r, g, b, a;
};
 
struct data {
        struct pw_main_loop *loop;
        struct spa_source *timer;
 
        struct pw_context *context;
        struct pw_core *core;
 
        struct pw_stream *stream;
        struct spa_hook stream_listener;
 
        struct spa_video_info_dsp format;
        int32_t stride;
        struct spa_io_position *position;
 
        int counter;
        uint32_t seq;
 
        double crop;
        double accumulator;
        int res;
};
 
static void draw_elipse(uint32_t *dst, int width, int height, uint32_t color)
{
        int i, j, r1, r2, r12, r22, r122;
 
        r1 = width/2;
        r12 = r1 * r1;
        r2 = height/2;
        r22 = r2 * r2;
        r122 = r12 * r22;
 
        for (i = -r2; i < r2; i++) {
                for (j = -r1; j < r1; j++) {
                        dst[(i + r2)*width+(j+r1)] =
                                (i * i * r12 + j * j * r22 <= r122) ? color : 0x00000000;
                }
        }
}
 
static inline float map_value(int value)
{
        return (value%256)/255.0f;
}
 
static void on_process(void *userdata)
{
        struct data *data = userdata;
        struct pw_buffer *b;
        struct spa_buffer *buf;
        uint32_t i, j;
        uint8_t *p;
        struct pixel *px;
        struct spa_meta *m;
        struct spa_meta_header *h;
        struct spa_meta_region *mc;
        struct spa_meta_cursor *mcs;
 
        if ((b = pw_stream_dequeue_buffer(data->stream)) == NULL) {
                pw_log_warn("out of buffers: %m");
                return;
        }
 
        buf = b->buffer;
        if ((p = buf->datas[0].data) == NULL)
                return;
 
        if ((h = spa_buffer_find_meta_data(buf, SPA_META_Header, sizeof(*h)))) {
#if 0
                struct timespec now;
                clock_gettime(CLOCK_MONOTONIC, &now);
                h->pts = SPA_TIMESPEC_TO_NSEC(&now);
#else
                h->pts = -1;
#endif
                h->flags = 0;
                h->seq = data->seq++;
                h->dts_offset = 0;
        }
        if ((m = spa_buffer_find_meta(buf, SPA_META_VideoDamage))) {
                struct spa_meta_region *r = spa_meta_first(m);
 
                if (spa_meta_check(r, m)) {
                        r->region.position = SPA_POINT(0,0);
                        r->region.size = data->position->video.size;
                        r++;
                }
                if (spa_meta_check(r, m))
                        r->region = SPA_REGION(0,0,0,0);
        }
        if ((mc = spa_buffer_find_meta_data(buf, SPA_META_VideoCrop, sizeof(*mc)))) {
                data->crop = (sin(data->accumulator) + 1.0) * 32.0;
                mc->region.position.x = data->crop;
                mc->region.position.y = data->crop;
                mc->region.size.width = data->position->video.size.width - data->crop*2;
                mc->region.size.height = data->position->video.size.height - data->crop*2;
        }
        if ((mcs = spa_buffer_find_meta_data(buf, SPA_META_Cursor, sizeof(*mcs)))) {
                struct spa_meta_bitmap *mb;
                uint32_t *bitmap, color;
 
                mcs->id = 1;
                mcs->position.x = (sin(data->accumulator) + 1.0) * 160.0 + 80;
                mcs->position.y = (cos(data->accumulator) + 1.0) * 100.0 + 50;
                mcs->hotspot.x = 0;
                mcs->hotspot.y = 0;
                mcs->bitmap_offset = sizeof(struct spa_meta_cursor);
 
                mb = SPA_PTROFF(mcs, mcs->bitmap_offset, struct spa_meta_bitmap);
                mb->format = SPA_VIDEO_FORMAT_ARGB;
                mb->size.width = CURSOR_WIDTH;
                mb->size.height = CURSOR_HEIGHT;
                mb->stride = CURSOR_WIDTH * CURSOR_BPP;
                mb->offset = sizeof(struct spa_meta_bitmap);
 
                bitmap = SPA_PTROFF(mb, mb->offset, uint32_t);
                color = (cos(data->accumulator) + 1.0) * (1 << 23);
                color |= 0xff000000;
 
                draw_elipse(bitmap, mb->size.width, mb->size.height, color);
        }
 
        for (i = 0; i < data->position->video.size.height; i++) {
                px = (struct pixel *)p;
                for (j = 0; j < data->position->video.size.width; j++) {
                        px[j] = (struct pixel){map_value(data->counter + j * i), map_value(data->counter + j * (i + 1)), map_value(data->counter + j * (i + 2)),  1.0f};
                }
                p += data->stride;
                data->counter += 13;
        }
 
        data->accumulator += M_PI_M2 / 50.0;
        if (data->accumulator >= M_PI_M2)
                data->accumulator -= M_PI_M2;
 
        buf->datas[0].chunk->offset = 0;
        buf->datas[0].chunk->size = data->position->video.size.height * data->stride;
        buf->datas[0].chunk->stride = data->stride;
 
        pw_stream_queue_buffer(data->stream, b);
}
 
static void on_timeout(void *userdata, uint64_t expirations)
{
        struct data *data = userdata;
        pw_log_trace("timeout");
        pw_stream_trigger_process(data->stream);
}
 
static void on_stream_state_changed(void *_data, enum pw_stream_state old, enum pw_stream_state state,
                                    const char *error)
{
        struct data *data = _data;
 
        printf("stream state: \"%s\"\n", pw_stream_state_as_string(state));
 
        switch (state) {
        case PW_STREAM_STATE_ERROR:
        case PW_STREAM_STATE_UNCONNECTED:
                pw_main_loop_quit(data->loop);
                break;
 
        case PW_STREAM_STATE_PAUSED:
                printf("node id: %d\n", pw_stream_get_node_id(data->stream));
                pw_loop_update_timer(pw_main_loop_get_loop(data->loop),
                                data->timer, NULL, NULL, false);
                break;
        case PW_STREAM_STATE_STREAMING:
        {
                struct timespec timeout, interval;
 
                timeout.tv_sec = 0;
                timeout.tv_nsec = 1;
                interval.tv_sec = 0;
                interval.tv_nsec = 40 * SPA_NSEC_PER_MSEC;
 
                pw_loop_update_timer(pw_main_loop_get_loop(data->loop),
                                data->timer, &timeout, &interval, false);
                break;
        }
        default:
                break;
        }
}
 
static void
on_stream_io_changed(void *_data, uint32_t id, void *area, uint32_t size)
{
        struct data *data = _data;
 
        switch (id) {
        case SPA_IO_Position:
                data->position = area;
                if (data->position)
                        pw_log_info("Position: %ux%u", data->position->video.size.width, data->position->video.size.height);
                break;
        }
}
 
static void
on_stream_param_changed(void *_data, uint32_t id, const struct spa_pod *param)
{
        struct data *data = _data;
        struct pw_stream *stream = data->stream;
        uint8_t params_buffer[1024];
        struct spa_pod_builder b = SPA_POD_BUILDER_INIT(params_buffer, sizeof(params_buffer));
        const struct spa_pod *params[5];
 
        if (param != NULL && id == SPA_PARAM_Tag) {
                spa_debug_pod(0, NULL, param);
                return;
        }
        if (param == NULL || id != SPA_PARAM_Format)
                return;
 
        spa_format_video_dsp_parse(param, &data->format);
 
        data->stride = SPA_ROUND_UP_N(data->position->video.size.width * BPP, 4);
 
        params[0] = spa_pod_builder_add_object(&b,
                SPA_TYPE_OBJECT_ParamBuffers, SPA_PARAM_Buffers,
                SPA_PARAM_BUFFERS_buffers, SPA_POD_CHOICE_RANGE_Int(8, 2, MAX_BUFFERS),
                SPA_PARAM_BUFFERS_blocks,  SPA_POD_Int(1),
                SPA_PARAM_BUFFERS_size,    SPA_POD_Int(data->stride * data->position->video.size.height),
                SPA_PARAM_BUFFERS_stride,  SPA_POD_Int(data->stride));
 
        params[1] = spa_pod_builder_add_object(&b,
                SPA_TYPE_OBJECT_ParamMeta, SPA_PARAM_Meta,
                SPA_PARAM_META_type, SPA_POD_Id(SPA_META_Header),
                SPA_PARAM_META_size, SPA_POD_Int(sizeof(struct spa_meta_header)));
 
        params[2] = spa_pod_builder_add_object(&b,
                SPA_TYPE_OBJECT_ParamMeta, SPA_PARAM_Meta,
                SPA_PARAM_META_type, SPA_POD_Id(SPA_META_VideoDamage),
                SPA_PARAM_META_size, SPA_POD_CHOICE_RANGE_Int(
                                        sizeof(struct spa_meta_region) * 16,
                                        sizeof(struct spa_meta_region) * 1,
                                        sizeof(struct spa_meta_region) * 16));
        params[3] = spa_pod_builder_add_object(&b,
                SPA_TYPE_OBJECT_ParamMeta, SPA_PARAM_Meta,
                SPA_PARAM_META_type, SPA_POD_Id(SPA_META_VideoCrop),
                SPA_PARAM_META_size, SPA_POD_Int(sizeof(struct spa_meta_region)));
#define CURSOR_META_SIZE(w,h)   (sizeof(struct spa_meta_cursor) + \
                                 sizeof(struct spa_meta_bitmap) + w * h * CURSOR_BPP)
        params[4] = spa_pod_builder_add_object(&b,
                SPA_TYPE_OBJECT_ParamMeta, SPA_PARAM_Meta,
                SPA_PARAM_META_type, SPA_POD_Id(SPA_META_Cursor),
                SPA_PARAM_META_size, SPA_POD_Int(
                        CURSOR_META_SIZE(CURSOR_WIDTH,CURSOR_HEIGHT)));
 
        pw_stream_update_params(stream, params, 5);
}
 
static void
on_trigger_done(void *_data)
{
        pw_log_trace("trigger done");
}
 
static const struct pw_stream_events stream_events = {
        PW_VERSION_STREAM_EVENTS,
        .process = on_process,
        .state_changed = on_stream_state_changed,
        .param_changed = on_stream_param_changed,
        .io_changed = on_stream_io_changed,
        .trigger_done = on_trigger_done,
};
 
static void do_quit(void *userdata, int signal_number)
{
        struct data *data = userdata;
        pw_main_loop_quit(data->loop);
}
 
int main(int argc, char *argv[])
{
        struct data data = { 0, };
        const struct spa_pod *params[2];
        uint8_t buffer[1024];
        struct spa_pod_builder b = SPA_POD_BUILDER_INIT(buffer, sizeof(buffer));
 
        pw_init(&argc, &argv);
 
        data.loop = pw_main_loop_new(NULL);
 
        pw_loop_add_signal(pw_main_loop_get_loop(data.loop), SIGINT, do_quit, &data);
        pw_loop_add_signal(pw_main_loop_get_loop(data.loop), SIGTERM, do_quit, &data);
 
        data.context = pw_context_new(pw_main_loop_get_loop(data.loop), NULL, 0);
 
        data.timer = pw_loop_add_timer(pw_main_loop_get_loop(data.loop), on_timeout, &data);
 
        data.core = pw_context_connect(data.context, NULL, 0);
        if (data.core == NULL) {
                fprintf(stderr, "can't connect: %m\n");
                data.res = -errno;
                goto cleanup;
        }
 
        data.stream = pw_stream_new(data.core, "video-src",
                pw_properties_new(
                        PW_KEY_MEDIA_CLASS, "Video/Source",
                        NULL));
 
        params[0] = spa_pod_builder_add_object(&b,
                SPA_TYPE_OBJECT_Format, SPA_PARAM_EnumFormat,
                SPA_FORMAT_mediaType,       SPA_POD_Id(SPA_MEDIA_TYPE_video),
                SPA_FORMAT_mediaSubtype,    SPA_POD_Id(SPA_MEDIA_SUBTYPE_dsp),
                SPA_FORMAT_VIDEO_format,    SPA_POD_Id(SPA_VIDEO_FORMAT_DSP_F32));
 
        {
                struct spa_pod_frame f;
                struct spa_dict_item items[1];
                /* send a tag, output tags travel downstream */
                spa_tag_build_start(&b, &f, SPA_PARAM_Tag, SPA_DIRECTION_OUTPUT);
                items[0] = SPA_DICT_ITEM_INIT("my-tag-key", "my-special-tag-value");
                spa_tag_build_add_dict(&b, &SPA_DICT_INIT(items, 1));
                params[1] = spa_tag_build_end(&b, &f);
        }
 
        pw_stream_add_listener(data.stream,
                               &data.stream_listener,
                               &stream_events,
                               &data);
 
        pw_stream_connect(data.stream,
                          PW_DIRECTION_OUTPUT,
                          PW_ID_ANY,
                          PW_STREAM_FLAG_DRIVER |
                          PW_STREAM_FLAG_MAP_BUFFERS,
                          params, 2);
 
        pw_main_loop_run(data.loop);
 
cleanup:
        pw_context_destroy(data.context);
        pw_main_loop_destroy(data.loop);
        pw_deinit();
 
        return data.res;
}