video-play-pull.c

Video input stream using pw_stream_trigger_process, for pull mode.

/* PipeWire */
/* SPDX-FileCopyrightText: Copyright © 2018 Wim Taymans */
/* SPDX-License-Identifier: MIT */
 
/*
 [title]
 Video input stream using \ref pw_stream_trigger_process, for pull mode.
 [title]
 */
 
#include <stdio.h>
#include <unistd.h>
#include <signal.h>
 
#include <spa/utils/result.h>
#include <spa/param/video/format-utils.h>
#include <spa/param/props.h>
#include <spa/debug/format.h>
 
#include <pipewire/pipewire.h>
 
#define WIDTH   640
#define HEIGHT  480
 
#define MAX_BUFFERS     64
 
#include "sdl.h"
 
struct pixel {
        float r, g, b, a;
};
 
struct data {
        const char *path;
 
        SDL_Renderer *renderer;
        SDL_Window *window;
        SDL_Texture *texture;
        SDL_Texture *cursor;
 
        struct pw_main_loop *loop;
        struct spa_source *timer;
 
        struct pw_stream *stream;
        struct spa_hook stream_listener;
 
        struct spa_io_position *position;
 
        struct spa_video_info format;
        int32_t stride;
        struct spa_rectangle size;
 
        int counter;
        SDL_Rect rect;
        SDL_Rect cursor_rect;
        bool is_yuv;
        bool have_request_process;
};
 
static void handle_events(struct data *data)
{
        SDL_Event event;
        while (SDL_PollEvent(&event)) {
                switch (event.type) {
                case SDL_QUIT:
                        pw_main_loop_quit(data->loop);
                        break;
                }
        }
}
 
/* our data processing function is in general:
 *
 *  struct pw_buffer *b;
 *  b = pw_stream_dequeue_buffer(stream);
 *
 *  .. do stuff with buffer ...
 *
 *  pw_stream_queue_buffer(stream, b);
 */
static void
on_process(void *_data)
{
        struct data *data = _data;
        struct pw_stream *stream = data->stream;
        struct pw_buffer *b;
        struct spa_buffer *buf;
        void *sdata, *ddata;
        int sstride, dstride, ostride;
        struct spa_meta_region *mc;
        struct spa_meta_cursor *mcs;
        uint32_t i, j;
        uint8_t *src, *dst;
        bool render_cursor = false;
 
        b = NULL;
        while (true) {
                struct pw_buffer *t;
                if ((t = pw_stream_dequeue_buffer(stream)) == NULL)
                        break;
                if (b)
                        pw_stream_queue_buffer(stream, b);
                b = t;
        }
        if (b == NULL) {
                pw_log_warn("out of buffers: %m");
                return;
        }
 
        buf = b->buffer;
 
        pw_log_trace("new buffer %p", buf);
 
        handle_events(data);
 
        if ((sdata = buf->datas[0].data) == NULL)
                goto done;
 
        /* get the videocrop metadata if any */
        if ((mc = spa_buffer_find_meta_data(buf, SPA_META_VideoCrop, sizeof(*mc))) &&
            spa_meta_region_is_valid(mc)) {
                data->rect.x = mc->region.position.x;
                data->rect.y = mc->region.position.y;
                data->rect.w = mc->region.size.width;
                data->rect.h = mc->region.size.height;
        }
        /* get cursor metadata */
        if ((mcs = spa_buffer_find_meta_data(buf, SPA_META_Cursor, sizeof(*mcs))) &&
            spa_meta_cursor_is_valid(mcs)) {
                struct spa_meta_bitmap *mb;
                void *cdata;
                int cstride;
 
                data->cursor_rect.x = mcs->position.x;
                data->cursor_rect.y = mcs->position.y;
 
                mb = SPA_PTROFF(mcs, mcs->bitmap_offset, struct spa_meta_bitmap);
                data->cursor_rect.w = mb->size.width;
                data->cursor_rect.h = mb->size.height;
 
                if (data->cursor == NULL) {
                        data->cursor = SDL_CreateTexture(data->renderer,
                                                 id_to_sdl_format(mb->format),
                                                 SDL_TEXTUREACCESS_STREAMING,
                                                 mb->size.width, mb->size.height);
                        SDL_SetTextureBlendMode(data->cursor, SDL_BLENDMODE_BLEND);
                }
 
 
                if (SDL_LockTexture(data->cursor, NULL, &cdata, &cstride) < 0) {
                        fprintf(stderr, "Couldn't lock cursor texture: %s\n", SDL_GetError());
                        goto done;
                }
 
                /* copy the cursor bitmap into the texture */
                src = SPA_PTROFF(mb, mb->offset, uint8_t);
                dst = cdata;
                ostride = SPA_MIN(cstride, mb->stride);
 
                for (i = 0; i < mb->size.height; i++) {
                        memcpy(dst, src, ostride);
                        dst += cstride;
                        src += mb->stride;
                }
                SDL_UnlockTexture(data->cursor);
 
                render_cursor = true;
        }
 
        /* copy video image in texture */
        if (data->is_yuv) {
                sstride = data->stride;
                SDL_UpdateYUVTexture(data->texture,
                                NULL,
                                sdata,
                                sstride,
                                SPA_PTROFF(sdata, sstride * data->size.height, void),
                                sstride / 2,
                                SPA_PTROFF(sdata, 5 * (sstride * data->size.height) / 4, void),
                                sstride / 2);
        }
        else {
                if (SDL_LockTexture(data->texture, NULL, &ddata, &dstride) < 0) {
                        fprintf(stderr, "Couldn't lock texture: %s\n", SDL_GetError());
                        goto done;
                }
 
                sstride = buf->datas[0].chunk->stride;
                if (sstride == 0)
                        sstride = buf->datas[0].chunk->size / data->size.height;
                ostride = SPA_MIN(sstride, dstride);
 
                src = sdata;
                dst = ddata;
 
                if (data->format.media_subtype == SPA_MEDIA_SUBTYPE_dsp) {
                        for (i = 0; i < data->size.height; i++) {
                                struct pixel *p = (struct pixel *) src;
                                for (j = 0; j < data->size.width; j++) {
                                        dst[j * 4 + 0] = SPA_CLAMP(p[j].r * 255.0f, 0, 255);
                                        dst[j * 4 + 1] = SPA_CLAMP(p[j].g * 255.0f, 0, 255);
                                        dst[j * 4 + 2] = SPA_CLAMP(p[j].b * 255.0f, 0, 255);
                                        dst[j * 4 + 3] = SPA_CLAMP(p[j].a * 255.0f, 0, 255);
                                }
                                src += sstride;
                                dst += dstride;
                        }
                } else {
                        for (i = 0; i < data->size.height; i++) {
                                memcpy(dst, src, ostride);
                                src += sstride;
                                dst += dstride;
                        }
                }
                SDL_UnlockTexture(data->texture);
        }
 
        SDL_RenderClear(data->renderer);
        /* now render the video and then the cursor if any */
        SDL_RenderCopy(data->renderer, data->texture, &data->rect, NULL);
        if (render_cursor) {
                SDL_RenderCopy(data->renderer, data->cursor, NULL, &data->cursor_rect);
        }
        SDL_RenderPresent(data->renderer);
 
      done:
        pw_stream_queue_buffer(stream, b);
}
 
static void enable_timeouts(struct data *data, bool enabled)
{
        struct timespec timeout, interval, *to, *iv;
 
        if (!enabled || data->have_request_process) {
                to = iv = NULL;
        } else {
                timeout.tv_sec = 0;
                timeout.tv_nsec = 1;
                interval.tv_sec = 0;
                interval.tv_nsec = 80 * SPA_NSEC_PER_MSEC;
                to = &timeout;
                iv = &interval;
        }
        pw_loop_update_timer(pw_main_loop_get_loop(data->loop),
                                data->timer, to, iv, false);
}
 
 
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;
        fprintf(stderr, "stream state: \"%s\"\n", pw_stream_state_as_string(state));
        switch (state) {
        case PW_STREAM_STATE_UNCONNECTED:
                pw_main_loop_quit(data->loop);
                break;
        case PW_STREAM_STATE_PAUSED:
                enable_timeouts(data, false);
                break;
        case PW_STREAM_STATE_STREAMING:
                enable_timeouts(data, true);
                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;
                break;
        }
}
 
static void
on_trigger_done(void *_data)
{
        struct data *data = _data;
        pw_log_trace("%p trigger done", data);
}
 
static void on_timeout(void *userdata, uint64_t expirations)
{
        struct data *data = userdata;
        if (!data->have_request_process)
                pw_stream_trigger_process(data->stream);
}
 
static void
on_command(void *_data, const struct spa_command *command)
{
        struct data *data = _data;
        switch (SPA_NODE_COMMAND_ID(command)) {
        case SPA_NODE_COMMAND_RequestProcess:
                data->have_request_process = true;
                enable_timeouts(data, false);
                pw_stream_trigger_process(data->stream);
                break;
        default:
                break;
        }
}
 
/* Be notified when the stream param changes. We're only looking at the
 * format changes.
 *
 * We are now supposed to call pw_stream_finish_format() with success or
 * failure, depending on if we can support the format. Because we gave
 * a list of supported formats, this should be ok.
 *
 * As part of pw_stream_finish_format() we can provide parameters that
 * will control the buffer memory allocation. This includes the metadata
 * that we would like on our buffer, the size, alignment, etc.
 */
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];
        Uint32 sdl_format;
        void *d;
        int32_t mult, size;
 
        /* NULL means to clear the format */
        if (param == NULL || id != SPA_PARAM_Format)
                return;
 
        fprintf(stderr, "got format:\n");
        spa_debug_format(2, NULL, param);
 
        if (spa_format_parse(param, &data->format.media_type, &data->format.media_subtype) < 0)
                return;
 
        if (data->format.media_type != SPA_MEDIA_TYPE_video)
                return;
 
        switch (data->format.media_subtype) {
        case SPA_MEDIA_SUBTYPE_raw:
                /* call a helper function to parse the format for us. */
                spa_format_video_raw_parse(param, &data->format.info.raw);
                sdl_format = id_to_sdl_format(data->format.info.raw.format);
                data->size = SPA_RECTANGLE(data->format.info.raw.size.width,
                                data->format.info.raw.size.height);
                mult = 1;
                break;
        case SPA_MEDIA_SUBTYPE_dsp:
                spa_format_video_dsp_parse(param, &data->format.info.dsp);
                if (data->format.info.dsp.format != SPA_VIDEO_FORMAT_DSP_F32)
                        return;
                sdl_format = SDL_PIXELFORMAT_RGBA32;
                data->size = SPA_RECTANGLE(data->position->video.size.width,
                                data->position->video.size.height);
                mult = 4;
                break;
        default:
                sdl_format = SDL_PIXELFORMAT_UNKNOWN;
                break;
        }
 
        if (sdl_format == SDL_PIXELFORMAT_UNKNOWN) {
                pw_stream_set_error(stream, -EINVAL, "unknown pixel format");
                return;
        }
        if (data->size.width == 0 || data->size.height == 0) {
                pw_stream_set_error(stream, -EINVAL, "invalid size");
                return;
        }
 
        data->texture = SDL_CreateTexture(data->renderer,
                                          sdl_format,
                                          SDL_TEXTUREACCESS_STREAMING,
                                          data->size.width,
                                          data->size.height);
        SDL_LockTexture(data->texture, NULL, &d, &data->stride);
        SDL_UnlockTexture(data->texture);
 
        switch(sdl_format) {
        case SDL_PIXELFORMAT_YV12:
        case SDL_PIXELFORMAT_IYUV:
                size = (data->stride * data->size.height) * 3 / 2;
                data->is_yuv = true;
                break;
        default:
                size = data->stride * data->size.height;
                break;
        }
 
        data->rect.x = 0;
        data->rect.y = 0;
        data->rect.w = data->size.width;
        data->rect.h = data->size.height;
 
        /* a SPA_TYPE_OBJECT_ParamBuffers object defines the acceptable size,
         * number, stride etc of the buffers */
        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(size * mult),
                SPA_PARAM_BUFFERS_stride,  SPA_POD_Int(data->stride * mult),
                SPA_PARAM_BUFFERS_dataType, SPA_POD_CHOICE_FLAGS_Int((1<<SPA_DATA_MemPtr)));
 
        /* a header metadata with timing information */
        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)));
        /* video cropping information */
        params[2] = 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 * 4)
        /* cursor information */
        params[3] = 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_CHOICE_RANGE_Int(
                                CURSOR_META_SIZE(64,64),
                                CURSOR_META_SIZE(1,1),
                                CURSOR_META_SIZE(256,256)));
 
        /* we are done */
        pw_stream_update_params(stream, params, 4);
}
 
/* these are the stream events we listen for */
static const struct pw_stream_events stream_events = {
        PW_VERSION_STREAM_EVENTS,
        .state_changed = on_stream_state_changed,
        .io_changed = on_stream_io_changed,
        .param_changed = on_stream_param_changed,
        .process = on_process,
        .trigger_done = on_trigger_done,
        .command = on_command,
};
 
static int build_format(struct data *data, struct spa_pod_builder *b, const struct spa_pod **params)
{
        SDL_RendererInfo info;
 
        SDL_GetRendererInfo(data->renderer, &info);
        params[0] = sdl_build_formats(&info, b);
 
        fprintf(stderr, "supported SDL formats:\n");
        spa_debug_format(2, NULL, params[0]);
 
        params[1] = 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));
 
        fprintf(stderr, "supported DSP formats:\n");
        spa_debug_format(2, NULL, params[1]);
 
        return 2;
}
 
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));
        struct pw_properties *props;
        int res, n_params;
 
        pw_init(&argc, &argv);
 
        /* create a main loop */
        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);
 
        /* the timer to pull in data */
        data.timer = pw_loop_add_timer(pw_main_loop_get_loop(data.loop), on_timeout, &data);
 
        /* create a simple stream, the simple stream manages to core and remote
         * objects for you if you don't need to deal with them
         *
         * If you plan to autoconnect your stream, you need to provide at least
         * media, category and role properties
         *
         * Pass your events and a user_data pointer as the last arguments. This
         * will inform you about the stream state. The most important event
         * you need to listen to is the process event where you need to consume
         * the data provided to you.
         */
        props = pw_properties_new(PW_KEY_MEDIA_TYPE, "Video",
                        PW_KEY_MEDIA_CATEGORY, "Capture",
                        PW_KEY_MEDIA_ROLE, "Camera",
                        PW_KEY_PRIORITY_DRIVER, "10000",
                        NULL),
        data.path = argc > 1 ? argv[1] : NULL;
        if (data.path)
                /* Set stream target if given on command line */
                pw_properties_set(props, PW_KEY_TARGET_OBJECT, data.path);
 
        data.stream = pw_stream_new_simple(
                        pw_main_loop_get_loop(data.loop),
                        "video-play",
                        props,
                        &stream_events,
                        &data);
 
        if (SDL_Init(SDL_INIT_VIDEO) < 0) {
                fprintf(stderr, "can't initialize SDL: %s\n", SDL_GetError());
                return -1;
        }
 
        if (SDL_CreateWindowAndRenderer
            (WIDTH, HEIGHT, SDL_WINDOW_RESIZABLE, &data.window, &data.renderer)) {
                fprintf(stderr, "can't create window: %s\n", SDL_GetError());
                return -1;
        }
 
        /* build the extra parameters to connect with. To connect, we can provide
         * a list of supported formats.  We use a builder that writes the param
         * object to the stack. */
        n_params = build_format(&data, &b, params);
 
        /* now connect the stream, we need a direction (input/output),
         * an optional target node to connect to, some flags and parameters
         */
        if ((res = pw_stream_connect(data.stream,
                          PW_DIRECTION_INPUT,
                          PW_ID_ANY,
                          PW_STREAM_FLAG_DRIVER |       /* we're driver, we pull */
                          PW_STREAM_FLAG_AUTOCONNECT |  /* try to automatically connect this stream */
                          PW_STREAM_FLAG_MAP_BUFFERS,   /* mmap the buffer data for us */
                          params, n_params))            /* extra parameters, see above */ < 0) {
                fprintf(stderr, "can't connect: %s\n", spa_strerror(res));
                return -1;
        }
 
        /* do things until we quit the mainloop */
        pw_main_loop_run(data.loop);
 
        pw_stream_destroy(data.stream);
        pw_main_loop_destroy(data.loop);
 
        SDL_DestroyTexture(data.texture);
        if (data.cursor)
                SDL_DestroyTexture(data.cursor);
        SDL_DestroyRenderer(data.renderer);
        SDL_DestroyWindow(data.window);
        pw_deinit();
 
        return 0;
}