从零开发一款Android Rtmp播放器

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}\n eglQuerySurface(ctx->display, ctx->surface, EGL_WIDTH, &ctx->width);\n eglQuerySurface(ctx->display, ctx->surface, EGL_HEIGHT, &ctx->height);\n initTexture(oar);\n\n oar_java_class * jc = oar->jc;\n JNIEnv * jniEnv = oar->video_render_ctx->jniEnv;\n jobject surface_texture = (*jniEnv)->CallStaticObjectMethod(jniEnv, jc->SurfaceTextureBridge, jc->texture_getSurface, ctx->texture[3]);\n ctx->texture_window = ANativeWindow_fromSurface(jniEnv, surface_texture);\n\n}\n","attrs":{}}]},{"type":"heading","attrs":{"align":null,"level":3},"content":[{"type":"text","text":"8.2 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*\n * @param oar\n * @param frame\n * @return 0 draw\n * -1 sleep 33ms continue\n * -2 break\n */\nstatic inline int draw_video_frame(oarplayer *oar) {\n // 上一次可能没有画， 这种情况就不需要取新的了\n if (oar->video_frame == NULL) {\n oar->video_frame = oar_frame_queue_get(oar->video_frame_queue);\n }\n // buffer empty ==> sleep 10ms , return 0\n // eos ==> return -2\n if (oar->video_frame == NULL) {\n _LOGD(\"video_frame is null...\");\n usleep(BUFFER_EMPTY_SLEEP_US);\n return 0;\n\n }\n int64_t time_stamp = oar->video_frame->pts;\n\n\n int64_t diff = 0;\n if(oar->metadata->has_audio){\n diff = time_stamp - (oar->audio_clock->pts + oar->audio_player_ctx->get_delta_time(oar->audio_player_ctx));\n }else{\n diff = time_stamp - oar_clock_get(oar->video_clock);\n }\n _LOGD(\"time_stamp:%lld, clock:%lld, diff:%lld\",time_stamp , oar_clock_get(oar->video_clock), diff);\n oar_model *model = oar->video_render_ctx->model;\n\n\n // diff >= 33ms if draw_mode == wait_frame return -1\n // if draw_mode == fixed_frequency draw previous frame ,return 0\n // diff > 0 && diff < 33ms sleep(diff) draw return 0\n // diff <= 0 draw return 0\n if (diff >= WAIT_FRAME_SLEEP_US) {\n if (oar->video_render_ctx->draw_mode == wait_frame) {\n return -1;\n } else {\n draw_now(oar->video_render_ctx);\n return 0;\n }\n } else {\n // if diff > WAIT_FRAME_SLEEP_US then use previous frame\n // else use current frame and release frame\n// LOGI(\"start draw...\");\n pthread_mutex_lock(oar->video_render_ctx->lock);\n model->update_frame(model, oar->video_frame);\n pthread_mutex_unlock(oar->video_render_ctx->lock);\n oar_player_release_video_frame(oar, oar->video_frame);\n\n JNIEnv * jniEnv = oar->video_render_ctx->jniEnv;\n (*jniEnv)->CallStaticVoidMethod(jniEnv, oar->jc->SurfaceTextureBridge, oar->jc->texture_updateTexImage);\n jfloatArray texture_matrix_array = (*jniEnv)->CallStaticObjectMethod(jniEnv, oar->jc->SurfaceTextureBridge, oar->jc->texture_getTransformMatrix);\n (*jniEnv)->GetFloatArrayRegion(jniEnv, 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ES接口、EGL接口、以及音视频相关知识。具体播放器代码可直接在官方地址查看：","attrs":{}},{"type":"link","attrs":{"href":"https://github.com/qingkouwei/oarplayer","title":"","type":null},"content":[{"type":"text","text":"oarplayer","attrs":{}}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/d5/d5f7a2a4122a611baad795eff149f9ce.jpeg","alt":null,"title":"","style":[{"key":"width","value":"100%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}}]}