ijkplayer-添加播放截图功能

应用播放的时候需要截图，可以在上层使用TexturView来使用截图，不过太具有局限性呢，还是在底层处理比较好。
那么先分析下可以在哪里加截图呢？看到网上很多做的都不能支持硬解截图，这样肯定是不行的。

所以我们可以选择在video_image_display2中来做截屏处理。

添加shot_screen.h

#ifndef _SHOT_SCREEN_H
#define _SHOT_SCREEN_H

#include <jni.h>
#include "ff_ffplay_def.h"
#include "ijkplayer.h"

int do_shot(VideoState *videoState, uint8_t *frameFuf, int destWidth, int destHeight,
            SDL_VoutOverlay *bmp);

jobject start_shot(JNIEnv *env, IjkMediaPlayer *mp, int width, int height, jobject config);

#endif

添加shot_screen.c文件

#include <jni.h>
#include <android/bitmap.h>
#include "ff_ffplay_def.h"
#include "ijkplayer.h"
#include "ijkplayer_internal.h"
#include "shot_screen.h"

void fill_bitmap(int lineSize, uint8_t *data, uint8_t *frameFuf, int width, int height) {
    int size = width * 4;
    for (int i = 0; i < height; i++) {
        memcpy(frameFuf + i * size, data + i * lineSize, (size_t) size);
    }
}

int scale_and_fill_bitmap(VideoState *videoState, uint8_t *frameFuf, int destWidth, int destHeight,
                          SDL_VoutOverlay *bmp, enum AVPixelFormat pixelFormat) {
    int ret = 0;
    int height = bmp->h;
    int width = bmp->w;

    struct SwsContext *swsContext = sws_getCachedContext(videoState->img_convert_ctx, width,
                                                         height,
                                                         pixelFormat, destWidth,
                                                         destHeight,
                                                         AV_PIX_FMT_RGBA, SWS_FAST_BILINEAR,
                                                         NULL, NULL, NULL);
    AVFrame *rgbFrame = av_frame_alloc();
    uint8_t *outBuffer = av_malloc(
            (size_t) av_image_get_buffer_size(AV_PIX_FMT_RGBA, destWidth, destHeight, 1));
    if (outBuffer == NULL) {
        ret = -1;
        goto end;
    }
    if (av_image_fill_arrays(rgbFrame->data, rgbFrame->linesize, outBuffer, AV_PIX_FMT_RGBA,
                             destWidth, destHeight, 1) < 0) {
        ret = -1;
        goto end;
    }
    int result = sws_scale(swsContext, (const uint8_t *const *) bmp->pixels,
                           (const int *) bmp->pitches, 0,
                           height, &frameFuf,
                           rgbFrame->linesize);
    if (result <= 0) {
        ret = -1;
        goto end;
    }
    end:
    av_frame_free(&rgbFrame);
    sws_freeContext(swsContext);
    if (outBuffer != NULL) {
        av_free(outBuffer);
    }
    return ret;
}

int do_shot(VideoState *videoState, uint8_t *frameFuf, int destWidth, int destHeight,
            SDL_VoutOverlay *bmp) {
    int height = bmp->h;
    int width = bmp->w;
    enum AVPixelFormat dst_format;
    int needScale = 0;
    switch (bmp->format) {
        case SDL_FCC_YV12:
        case SDL_FCC_I420:
            dst_format = AV_PIX_FMT_YUV420P;
            needScale = 1;
            break;
        case SDL_FCC_I444P10LE:
            dst_format = AV_PIX_FMT_YUV444P10LE;
            needScale = 1;
            break;
        case SDL_FCC_RV32:
            dst_format = AV_PIX_FMT_0BGR32;
            break;
        case SDL_FCC_RV24:
            dst_format = AV_PIX_FMT_RGB24;
            needScale = 1;
            break;
        case SDL_FCC_RV16:
            dst_format = AV_PIX_FMT_RGB565;
            break;
        default:
            return -1;
    }
    if (destWidth != width || destHeight != height || needScale) {
        return scale_and_fill_bitmap(videoState, frameFuf, destWidth, destHeight, bmp, dst_format);
    }
    int lineSize = bmp->pitches[0];
    uint8_t *data = bmp->pixels[0];
    fill_bitmap(lineSize, data, frameFuf, width, height);
    return 0;
}

SDL_VoutOverlay *get_last_bmp(FFPlayer *ffp) {
    VideoState *is = ffp->is;
    Frame *vp = &is->pictq.queue[is->pictq.rindex];
    return vp->bmp;
}

jobject start_shot(JNIEnv *env, IjkMediaPlayer *mp, int width, int height, jobject config) {
    SDL_VoutOverlay *bmp = get_last_bmp(mp->ffplayer);
	if (bmp == NULL) {
        return NULL;
    }
    jclass bitmapClass = (*env)->FindClass(env, "android/graphics/Bitmap");
    jmethodID createBitmapMethodId = (*env)->GetStaticMethodID(env, bitmapClass, "createBitmap",
                                                               "(IILandroid/graphics/Bitmap$Config;)Landroid/graphics/Bitmap;");
    int destWidth = bmp->w;
    if (width > 0) {
        destWidth = width >= destWidth ? destWidth : width;
    }
    int destHeight = bmp->h;
    if (height > 0) {
        destHeight = height >= destHeight ? destHeight : height;
    }
    jobject bitmap = (*env)->CallStaticObjectMethod(env, bitmapClass, createBitmapMethodId,
                                                    destWidth,
                                                    destHeight, config);
    uint8_t *frameBuffer = NULL;
    if (0 > AndroidBitmap_lockPixels(env, bitmap, (void **) &frameBuffer)) {
        return NULL;
    }
    int ret = do_shot(mp->ffplayer->is, frameBuffer, destWidth, destHeight, bmp);
    if (0 > AndroidBitmap_unlockPixels(env, bitmap)) {
        return NULL;
    }
    ijkmp_dec_ref_p(&mp);
    if (ret < 0) {
        return NULL;
    }
    return bitmap;
}