libopenjpegenc: stop reusing image data buffer for openjpeg 2

openjpeg 2 sets the data pointers of the image components to NULL,
causing segfaults if the image is reused.

Reviewed-by: Michael Bradshaw <mjbshaw@gmail.com>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
(cherry picked from commit 69c8505f3b)
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>

libavcodec/libopenjpegenc.c

@@ -52,7 +52,9 @@
 
 typedef struct LibOpenJPEGContext {
     AVClass *avclass;
+#if OPENJPEG_MAJOR_VERSION == 1
     opj_image_t *image;
+#endif // OPENJPEG_MAJOR_VERSION == 1
     opj_cparameters_t enc_params;
 #if OPENJPEG_MAJOR_VERSION == 1
     opj_event_mgr_t event_mgr;
@@ -369,18 +371,22 @@ static av_cold int libopenjpeg_encode_init(AVCodecContext *avctx)
         cinema_parameters(&ctx->enc_params);
     }
 
+#if OPENJPEG_MAJOR_VERSION == 1
     ctx->image = mj2_create_image(avctx, &ctx->enc_params);
     if (!ctx->image) {
         av_log(avctx, AV_LOG_ERROR, "Error creating the mj2 image\n");
         err = AVERROR(EINVAL);
         goto fail;
     }
+#endif // OPENJPEG_MAJOR_VERSION == 1
 
     return 0;
 
 fail:
+#if OPENJPEG_MAJOR_VERSION == 1
     opj_image_destroy(ctx->image);
     ctx->image = NULL;
+#endif // OPENJPEG_MAJOR_VERSION == 1
     return err;
 }
 
@@ -591,18 +597,24 @@ static int libopenjpeg_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
                                     const AVFrame *frame, int *got_packet)
 {
     LibOpenJPEGContext *ctx = avctx->priv_data;
-    opj_image_t *image      = ctx->image;
+    int ret;
+    AVFrame *gbrframe;
+    int cpyresult = 0;
 #if OPENJPEG_MAJOR_VERSION == 1
+    opj_image_t *image      = ctx->image;
     opj_cinfo_t *compress   = NULL;
     opj_cio_t *stream       = NULL;
     int len;
 #else // OPENJPEG_MAJOR_VERSION == 2
     opj_codec_t *compress   = NULL;
     opj_stream_t *stream    = NULL;
+    opj_image_t *image      = mj2_create_image(avctx, &ctx->enc_params);
+    if (!image) {
+        av_log(avctx, AV_LOG_ERROR, "Error creating the mj2 image\n");
+        ret = AVERROR(EINVAL);
+        goto done;
+    }
 #endif // OPENJPEG_MAJOR_VERSION == 1
-    int cpyresult = 0;
-    int ret;
-    AVFrame *gbrframe;
 
     switch (avctx->pix_fmt) {
     case AV_PIX_FMT_RGB24:
@@ -625,8 +637,10 @@ static int libopenjpeg_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
     case AV_PIX_FMT_GBRP14:
     case AV_PIX_FMT_GBRP16:
         gbrframe = av_frame_clone(frame);
-        if (!gbrframe)
-            return AVERROR(ENOMEM);
+        if (!gbrframe) {
+            ret = AVERROR(ENOMEM);
+            goto done;
+        }
         gbrframe->data[0] = frame->data[2]; // swap to be rgb
         gbrframe->data[1] = frame->data[0];
         gbrframe->data[2] = frame->data[1];
@@ -683,19 +697,21 @@ static int libopenjpeg_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
         av_log(avctx, AV_LOG_ERROR,
                "The frame's pixel format '%s' is not supported\n",
                av_get_pix_fmt_name(avctx->pix_fmt));
-        return AVERROR(EINVAL);
+        ret = AVERROR(EINVAL);
+        goto done;
         break;
     }
 
     if (!cpyresult) {
         av_log(avctx, AV_LOG_ERROR,
                "Could not copy the frame data to the internal image buffer\n");
-        return -1;
+        ret = -1;
+        goto done;
     }
 
 #if OPENJPEG_MAJOR_VERSION == 2
     if ((ret = ff_alloc_packet2(avctx, pkt, 1024, 0)) < 0) {
-        return ret;
+        goto done;
     }
 #endif // OPENJPEG_MAJOR_VERSION == 2
 
@@ -762,7 +778,7 @@ static int libopenjpeg_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
 #error Missing call to opj_stream_set_user_data
 #endif
 
-    if (!opj_start_compress(compress, ctx->image, stream) ||
+    if (!opj_start_compress(compress, image, stream) ||
         !opj_encode(compress, stream) ||
         !opj_end_compress(compress, stream)) {
         av_log(avctx, AV_LOG_ERROR, "Error during the opj encode\n");
@@ -781,6 +797,7 @@ done:
 #if OPENJPEG_MAJOR_VERSION == 2
     opj_stream_destroy(stream);
     opj_destroy_codec(compress);
+    opj_image_destroy(image);
 #else
     opj_cio_close(stream);
     opj_destroy_compress(compress);
@@ -790,10 +807,12 @@ done:
 
 static av_cold int libopenjpeg_encode_close(AVCodecContext *avctx)
 {
+#if OPENJPEG_MAJOR_VERSION == 1
     LibOpenJPEGContext *ctx = avctx->priv_data;
 
     opj_image_destroy(ctx->image);
     ctx->image = NULL;
+#endif // OPENJPEG_MAJOR_VERSION == 1
     return 0;
 }