[FFmpeg-devel,2/3] avcodec/libjxlenc: Move image initialization code into libjxl_encode_init_image

diff --git a/libavcodec/libjxlenc.c b/libavcodec/libjxlenc.c
index 92a458d51a..6110c42a7c 100644
--- a/libavcodec/libjxlenc.c
+++ b/libavcodec/libjxlenc.c
@@ -50,6 +50,9 @@  typedef struct LibJxlEncodeContext {
     JxlEncoder *encoder;
     JxlEncoderFrameSettings *options;
     JxlBasicInfo info;
+    JxlPixelFormat jxl_fmt;
+    int animated;
+    int first_frame;
     int effort;
     float distance;
     int modular;
@@ -181,6 +184,9 @@  static av_cold int libjxl_encode_init(AVCodecContext *avctx)
         return AVERROR(ENOMEM);
     }
 
+    ctx->animated = 0;
+    ctx->first_frame = 1;
+
     return 0;
 }
 
@@ -235,28 +241,19 @@  static int libjxl_populate_primaries(void *avctx, JxlColorEncoding *jxl_color, e
     return 0;
 }
 
-/**
- * Encode an entire frame. Currently animation, is not supported by
- * this encoder, so this will always reinitialize a new still image
- * and encode a one-frame image (for image2 and image2pipe).
- */
-static int libjxl_encode_frame(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *frame, int *got_packet)
+static int libjxl_encode_init_image(AVCodecContext *avctx, const AVFrame *frame)
 {
     LibJxlEncodeContext *ctx = avctx->priv_data;
-    AVFrameSideData *sd;
-    const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(frame->format);
+    int ret;
     JxlBasicInfo *info = &ctx->info;
+    JxlPixelFormat *jxl_fmt = &ctx->jxl_fmt;
     JxlColorEncoding jxl_color;
-    JxlPixelFormat jxl_fmt;
     int bits_per_sample;
 #if JPEGXL_NUMERIC_VERSION >= JPEGXL_COMPUTE_NUMERIC_VERSION(0, 8, 0)
     JxlBitDepth jxl_bit_depth;
 #endif
-    JxlEncoderStatus jret;
-    int ret;
-    size_t available = ctx->buffer_size;
-    size_t bytes_written = 0;
-    uint8_t *next_out = ctx->buffer;
+    const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(frame->format);
+    AVFrameSideData *sd;
 
     /* reset the encoder every frame for image2 muxer */
     JxlEncoderReset(ctx->encoder);
@@ -269,23 +266,23 @@  static int libjxl_encode_frame(AVCodecContext *avctx, AVPacket *pkt, const AVFra
 
     /* populate the basic info settings */
     JxlEncoderInitBasicInfo(info);
-    jxl_fmt.num_channels = pix_desc->nb_components;
+    jxl_fmt->num_channels = pix_desc->nb_components;
     info->xsize = frame->width;
     info->ysize = frame->height;
-    info->num_extra_channels = (jxl_fmt.num_channels + 1) % 2;
-    info->num_color_channels = jxl_fmt.num_channels - info->num_extra_channels;
-    bits_per_sample = av_get_bits_per_pixel(pix_desc) / jxl_fmt.num_channels;
+    info->num_extra_channels = (jxl_fmt->num_channels + 1) % 2;
+    info->num_color_channels = jxl_fmt->num_channels - info->num_extra_channels;
+    bits_per_sample = av_get_bits_per_pixel(pix_desc) / jxl_fmt->num_channels;
     info->bits_per_sample = avctx->bits_per_raw_sample > 0 && !(pix_desc->flags & AV_PIX_FMT_FLAG_FLOAT)
                            ? avctx->bits_per_raw_sample : bits_per_sample;
     info->alpha_bits = (info->num_extra_channels > 0) * info->bits_per_sample;
     if (pix_desc->flags & AV_PIX_FMT_FLAG_FLOAT) {
         info->exponent_bits_per_sample = info->bits_per_sample > 16 ? 8 : 5;
         info->alpha_exponent_bits = info->alpha_bits ? info->exponent_bits_per_sample : 0;
-        jxl_fmt.data_type = info->bits_per_sample > 16 ? JXL_TYPE_FLOAT : JXL_TYPE_FLOAT16;
+        jxl_fmt->data_type = info->bits_per_sample > 16 ? JXL_TYPE_FLOAT : JXL_TYPE_FLOAT16;
     } else {
         info->exponent_bits_per_sample = 0;
         info->alpha_exponent_bits = 0;
-        jxl_fmt.data_type = info->bits_per_sample <= 8 ? JXL_TYPE_UINT8 : JXL_TYPE_UINT16;
+        jxl_fmt->data_type = info->bits_per_sample <= 8 ? JXL_TYPE_UINT8 : JXL_TYPE_UINT16;
     }
 
 #if JPEGXL_NUMERIC_VERSION >= JPEGXL_COMPUTE_NUMERIC_VERSION(0, 8, 0)
@@ -383,17 +380,41 @@  static int libjxl_encode_frame(AVCodecContext *avctx, AVPacket *pkt, const AVFra
             av_log(avctx, AV_LOG_WARNING, "Could not increase codestream level\n");
     }
 
-    jxl_fmt.endianness = JXL_NATIVE_ENDIAN;
-    jxl_fmt.align = frame->linesize[0];
+    jxl_fmt->endianness = JXL_NATIVE_ENDIAN;
+    jxl_fmt->align = frame->linesize[0];
+
+    return 0;
+}
+
+/**
+ * Encode an entire frame. Currently animation, is not supported by
+ * this encoder, so this will always reinitialize a new still image
+ * and encode a one-frame image (for image2 and image2pipe).
+ */
+static int libjxl_encode_frame(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *frame, int *got_packet)
+{
+    LibJxlEncodeContext *ctx = avctx->priv_data;
+    JxlEncoderStatus jret;
+    JxlBasicInfo *info = &ctx->info;
+    JxlPixelFormat *jxl_fmt = &ctx->jxl_fmt;
+    int ret;
+    size_t available = ctx->buffer_size;
+    size_t bytes_written = 0;
+    uint8_t *next_out = ctx->buffer;
+
+    if(!ctx->animated || ctx->first_frame) {
+        if((ret = libjxl_encode_init_image(avctx, frame)) < 0)
+            return ret;
+        ctx->first_frame = 0;
+    }
 
-    if (JxlEncoderAddImageFrame(ctx->options, &jxl_fmt, frame->data[0], jxl_fmt.align * info->ysize) != JXL_ENC_SUCCESS) {
+    if (JxlEncoderAddImageFrame(ctx->options, jxl_fmt, frame->data[0], jxl_fmt->align * info->ysize) != JXL_ENC_SUCCESS) {
         av_log(avctx, AV_LOG_ERROR, "Failed to add Image Frame\n");
         return AVERROR_EXTERNAL;
     }
 
     /*
      * Run this after the last frame in the image has been passed.
-     * TODO support animation
      */
     JxlEncoderCloseInput(ctx->encoder);