开发环境安装：
1，执行："sudo apt-get build-dep libsdl1.2"，确定依赖库都装全了。
sdl2.0没有正式发布到ubuntu，使用下面方法安装：
https://launchpad.net/~zoogie/+archive/sdl2-snapshots
sudo apt-add-repository ppa:zoogie/sdl2-snapshots
sudo apt-get update
sudo apt-get install libsdl2 libsdl2-dbg libsdl2-dev libsdl2-image libsdl2-image-dev libsdl2-ttf libsdl2-ttf-dev libsdl2-mixer libsdl2-mixer-dev
(在ubuntu 13.10 中，依赖库： sudo apt-get build-dep libsdl2）
2， vlc的安装
sudo apt-get install libvlc-dev
3，运行示例代码
// libSDL and libVLC sample code.
// License: [http://en.wikipedia.org/wiki/WTFPL WTFPL]
#include <stdio.h>
#include <stdint.h>
#include <math.h>
#include <stdlib.h>
#include <assert.h>
#include "SDL/SDL.h"
#include "SDL/SDL_mutex.h"
#include "vlc/vlc.h"
#define WIDTH 640
#define HEIGHT 480
#define VIDEOWIDTH 320
#define VIDEOHEIGHT 240
struct context {
SDL_Renderer *renderer;
SDL_Texture *texture;
SDL_mutex *mutex;
int n;
};
// VLC prepares to render a video frame.
static void *lock(void *data, void **p_pixels) {
struct context *c = (context *)data;
int pitch;
SDL_LockMutex(c->mutex);
SDL_LockTexture(c->texture, NULL, p_pixels, &pitch);
return NULL; // Picture identifier, not needed here.
}
// VLC just rendered a video frame.
static void unlock(void *data, void *id, void *const *p_pixels) {
struct context *c = (context *)data;
uint16_t *pixels = (uint16_t *)*p_pixels;
// We can also render stuff.
int x, y;
for(y = 10; y < 40; y++) {
for(x = 10; x < 40; x++) {
if(x < 13 || y < 13 || x > 36 || y > 36) {
pixels[y * VIDEOWIDTH + x] = 0xffff;
} else {
// RV16 = 5+6+5 pixels per color, BGR.
pixels[y * VIDEOWIDTH + x] = 0x02ff;
}
}
}
SDL_UnlockTexture(c->texture);
SDL_UnlockMutex(c->mutex);
}
// VLC wants to display a video frame.
static void display(void *data, void *id) {
struct context *c = (context *)data;
SDL_Rect rect;
rect.w = VIDEOWIDTH;
rect.h = VIDEOHEIGHT;
rect.x = (int)((1. + .5 * sin(0.03 * c->n)) * (WIDTH - VIDEOWIDTH) / 2);
rect.y = (int)((1. + .5 * cos(0.03 * c->n)) * (HEIGHT - VIDEOHEIGHT) / 2);
SDL_SetRenderDrawColor(c->renderer, 0, 80, 0, 255);
SDL_RenderClear(c->renderer);
SDL_RenderCopy(c->renderer, c->texture, NULL, &rect);
SDL_RenderPresent(c->renderer);
}
static void quit(int c) {
SDL_Quit();
exit(c);
}
int main(int argc, char *argv[]) {
libvlc_instance_t *libvlc;
libvlc_media_t *m;
libvlc_media_player_t *mp;
char const *vlc_argv[] = {
"--no-audio", // Don't play audio.
"--no-xlib", // Don't use Xlib.
// Apply a video filter.
//"--video-filter", "sepia",
//"--sepia-intensity=200"
};
int vlc_argc = sizeof(vlc_argv) / sizeof(*vlc_argv);
SDL_Event event;
int done = 0, action = 0, pause = 0, n = 0;
struct context context;
if(argc < 2) {
printf("Usage: %s <filename>
", argv[0]);
return EXIT_FAILURE;
}
// Initialise libSDL.
if(SDL_Init(SDL_INIT_VIDEO) < 0) {
printf("Could not initialize SDL: %s.
", SDL_GetError());
return EXIT_FAILURE;
}
// Create SDL graphics objects.
SDL_Window * window = SDL_CreateWindow(
"Fartplayer",
SDL_WINDOWPOS_UNDEFINED,
SDL_WINDOWPOS_UNDEFINED,
WIDTH, HEIGHT,
SDL_WINDOW_SHOWN|SDL_WINDOW_RESIZABLE);
if (!window) {
fprintf(stderr, "Couldn't create window: %s
", SDL_GetError());
quit(3);
}
context.renderer = SDL_CreateRenderer(window, -1, 0);
if (!context.renderer) {
fprintf(stderr, "Couldn't create renderer: %s
", SDL_GetError());
quit(4);
}
context.texture = SDL_CreateTexture(
context.renderer,
SDL_PIXELFORMAT_BGR565, SDL_TEXTUREACCESS_STREAMING,
VIDEOWIDTH, VIDEOHEIGHT);
if (!context.texture) {
fprintf(stderr, "Couldn't create texture: %s
", SDL_GetError());
quit(5);
}
context.mutex = SDL_CreateMutex();
// If you don't have this variable set you must have plugins directory
// with the executable or libvlc_new() will not work!
printf("VLC_PLUGIN_PATH=%s
", getenv("VLC_PLUGIN_PATH"));
// Initialise libVLC.
libvlc = libvlc_new(vlc_argc, vlc_argv);
if(NULL == libvlc) {
printf("LibVLC initialization failure.
");
return EXIT_FAILURE;
}
m = libvlc_media_new_path(libvlc, argv[1]);
mp = libvlc_media_player_new_from_media(m);
libvlc_media_release(m);
libvlc_video_set_callbacks(mp, lock, unlock, display, &context);
libvlc_video_set_format(mp, "RV16", VIDEOWIDTH, VIDEOHEIGHT, VIDEOWIDTH*2);
libvlc_media_player_play(mp);
// Main loop.
while(!done) {
action = 0;
// Keys: enter (fullscreen), space (pause), escape (quit).
while( SDL_PollEvent( &event )) {
switch(event.type) {
case SDL_QUIT:
done = 1;
break;
case SDL_KEYDOWN:
action = event.key.keysym.sym;
break;
}
}
switch(action) {
case SDLK_ESCAPE:
case SDLK_q:
done = 1;
break;
case ' ':
printf("Pause toggle.
");
pause = !pause;
break;
}
if(!pause) { context.n++; }
SDL_Delay(1000/10);
}
// Stop stream and clean up libVLC.
libvlc_media_player_stop(mp);
libvlc_media_player_release(mp);
libvlc_release(libvlc);
// Close window and clean up libSDL.
SDL_DestroyMutex(context.mutex);
SDL_DestroyRenderer(context.renderer);
quit(0);
return 0;
}
显示上是黑屏。没有视频显示。
后修改代码测试：
将struct context context; 放到全局。在display回调里面用全局render fill rect。在main循环里面也用同样的代码画方框。结果main中的方框可以画出。从vlc回调回的display画方框无法显示。
#include <stdio.h>
#include <stdint.h>
#include <math.h>
#include <stdlib.h>
#include <assert.h>
#include <SDL2/SDL.h>
#include <SDL2/SDL_mutex.h>
#include <vlc/vlc.h>
#define WIDTH 640
#define HEIGHT 480
#define VIDEOWIDTH 320
#define VIDEOHEIGHT 240
struct context {
SDL_Renderer *renderer;
SDL_Texture *texture;
SDL_mutex *mutex;
int n;
};
struct context context;
// VLC prepares to render a video frame.
static void *lock(void *data, void **p_pixels) {
struct context *c = &context;
int pitch;
SDL_LockMutex(c->mutex);
SDL_LockTexture(c->texture, NULL, p_pixels, &pitch);
return NULL ; // Picture identifier, not needed here.
}
// VLC just rendered a video frame.
static void unlock(void *data, void *id, void * const *p_pixels) {
struct context *c = &context;
uint16_t *pixels = (uint16_t *) *p_pixels;
/*
// We can also render stuff.
int x, y;
for (y = 10; y < 40; y++) {
for (x = 10; x < 40; x++) {
if (x < 13 || y < 13 || x > 36 || y > 36) {
pixels[y * VIDEOWIDTH + x] = 0xffff;
} else {
// RV16 = 5+6+5 pixels per color, BGR.
pixels[y * VIDEOWIDTH + x] = 0x02ff;
}
}
}
*/
SDL_UnlockTexture(c->texture);
SDL_UnlockMutex(c->mutex);
}
void draw(SDL_Rect *rect) {
SDL_SetRenderDrawColor(context.renderer, rand() % 240, rand() % 240, rand() % 240, 0);
// SDL_RenderClear(context.renderer);
// SDL_RenderCopy(context.renderer, context.texture, NULL, rect);
SDL_RenderFillRect(context.renderer, rect);
}
// VLC wants to display a video frame.
static void display(void *data, void *id) {
printf("================================
");
SDL_Rect rect;
rect.w = VIDEOWIDTH;
rect.h = VIDEOHEIGHT;
rect.x = 0;
rect.y = 0;
draw(&rect);
SDL_RenderPresent(context.renderer);
SDL_Delay(3000);
}
static void quit(int c) {
SDL_Quit();
exit(c);
}
int main(int argc, char *argv[]) {
libvlc_instance_t *libvlc;
libvlc_media_t *m;
libvlc_media_player_t *mp;
char const *vlc_argv[] = { "-vvv", "--no-audio", // Don't play audio.
"--no-xlib", // Don't use Xlib.
// Apply a video filter.
//"--video-filter", "sepia",
//"--sepia-intensity=200"
};
int vlc_argc = sizeof(vlc_argv) / sizeof(*vlc_argv);
SDL_Event event;
int done = 0, action = 0, pause = 0, n = 0;
// if(argc < 2) {
// printf("Usage: %s <filename>
", argv[0]);
// return EXIT_FAILURE;
// }
// Initialise libSDL.
if (SDL_Init(SDL_INIT_VIDEO) < 0) {
printf("Could not initialize SDL: %s.
", SDL_GetError());
return EXIT_FAILURE;
}
// Create SDL graphics objects.
SDL_Window * window = SDL_CreateWindow("Fartplayer", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, WIDTH, HEIGHT,
SDL_WINDOW_SHOWN | SDL_WINDOW_RESIZABLE);
if (!window) {
fprintf(stderr, "Couldn't create window: %s
", SDL_GetError());
quit(3);
}
context.renderer = SDL_CreateRenderer(window, 1, 0);
if (!context.renderer) {
fprintf(stderr, "Couldn't create renderer: %s
", SDL_GetError());
quit(4);
}
context.texture = SDL_CreateTexture(context.renderer, SDL_PIXELFORMAT_BGR565, SDL_TEXTUREACCESS_STREAMING, VIDEOWIDTH, VIDEOHEIGHT);
if (!context.texture) {
fprintf(stderr, "Couldn't create texture: %s
", SDL_GetError());
quit(5);
}
context.mutex = SDL_CreateMutex();
// If you don't have this variable set you must have plugins directory
// with the executable or libvlc_new() will not work!
printf("VLC_PLUGIN_PATH=%s
", getenv("VLC_PLUGIN_PATH"));
// Initialise libVLC.
libvlc = libvlc_new(vlc_argc, vlc_argv);
if (NULL == libvlc) {
printf("LibVLC initialization failure.
");
return EXIT_FAILURE;
}
m = libvlc_media_new_path(libvlc, "./test.mp4");
mp = libvlc_media_player_new_from_media(m);
libvlc_media_release(m);
libvlc_video_set_callbacks(mp, lock, unlock, display, &context);
libvlc_video_set_format(mp, "RV16", VIDEOWIDTH, VIDEOHEIGHT, VIDEOWIDTH * 2);
libvlc_media_player_play(mp);
// Main loop.
while (!done) {
action = 0;
// Keys: enter (fullscreen), space (pause), escape (quit).
while (SDL_PollEvent(&event)) {
switch (event.type) {
case SDL_QUIT:
done = 1;
break;
case SDL_KEYDOWN:
action = event.key.keysym.sym;
break;
}
}
switch (action) {
case SDLK_ESCAPE:
case SDLK_q:
done = 1;
break;
case ' ':
printf("Pause toggle.
");
pause = !pause;
break;
}
if (!pause) {
context.n++;
}
SDL_Rect rect;
rect.w = VIDEOWIDTH;
rect.h = VIDEOHEIGHT;
rect.x = VIDEOWIDTH;
rect.y = VIDEOHEIGHT;
draw(&rect);
SDL_RenderPresent(context.renderer);
SDL_Delay(3000);
}
// Stop stream and clean up libVLC.
libvlc_media_player_stop(mp);
libvlc_media_player_release(mp);
libvlc_release(libvlc);
// Close window and clean up libSDL.
SDL_DestroyMutex(context.mutex);
SDL_DestroyRenderer(context.renderer);
quit(0);
return 0;
}
单步跟踪后，发现render infor里面是opengl。将
context.renderer = SDL_CreateRenderer(window, -1, 0);
改成context.renderer = SDL_CreateRenderer(window, 1, 0);后，可以正常播放。
可以打印出所有 render 信息：
int nRenderDrivers = SDL_GetNumRenderDrivers();
int i = 0;
for (; i < nRenderDrivers; i++) {
SDL_RendererInfo info;
SDL_GetRenderDriverInfo(i, &info); //d3d
printf("====info name %d: %s =====
", i, info.name);
printf("====max_texture_height %d =====
", i, info.max_texture_height);
printf("====max_texture_width %d =====
", i, info.max_texture_width);
}
————————————————————————————
When you build SDL2, make sure that when you run the initial cmake
step that all the video options are marked as ON, including
VIDEO_OPENGL and VIDEO_X11_*.
A quick way to make sure you've got all the dependencies you need is
to run "sudo apt-get build-dep libsdl1.2"; this installs the list of
build prerequisites for Ubuntu's SDL 1.2 package, which are more or
less unchanged for SDL2. I believe it's libgl1-mesa-dev which contains
the OpenGL headers.
*** remove unity ****
sudo apt-get purge unity unity-2d unity-2d-common unity-2d-panel unity-2d-shell unity-2d-spread unity-asset-pool unity-common unity-lens-applications unity-lens-files unity-lens-music unity-lens-video unity-scope-musicstores unity-scope-video-remote unity-services indicator-messages indicator-status-provider-mc5 appmenu-qt appmenu-gtk appmenu-gtk3 lightdm unity-greeter overlay-scrollbar zeitgeist zeitgeist-core zeitgeist-datahub activity-log-manager-common activity-log-manager-control-center
sudo apt-get purge unity unity-2d unity-2d-common unity-2d-panel unity-2d-shell unity-2d-spread unity-asset-pool unity-common unity-lens-applications unity-lens-files unity-lens-music unity-lens-video unity-scope-musicstores unity-scope-video-remote unity-services indicator-messages indicator-status-provider-mc5 appmenu-qt appmenu-gtk appmenu-gtk3 lightdm unity-greeter overlay-scrollbar zeitgeist zeitgeist-core zeitgeist-datahub activity-log-manager-common activity-log-manager-control-center
ensure that SDL2 has full OpenGL and X support
sudo apt install build-essential xorg-dev libudev-dev libts-dev libgl1-mesa-dev libglu1-mesa-dev libasound2-dev libpulse-dev libopenal-dev libogg-dev libvorbis-dev libaudiofile-dev libpng12-dev libfreetype6-dev libusb-dev libdbus-1-dev zlib1g-dev libdirectfb-devVLC 源码编译参考：
sudo apt-get install git libtool build-essential pkg-config autoconf
sudo apt-get build-dep vlc