X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fpngenc.c;h=947c7e147b9a63bd4b4bb41efc18aae9398a1f7e;hb=eeb55f5f2f48dba3cb4530e9c65999471affe26e;hp=630b8e35972fdd8e5d4e8a6d849fdffa0ff3ef6f;hpb=83c7fe324584e747be016ccffa760fac346db1a8;p=ffmpeg

diff --git a/libavcodec/pngenc.c b/libavcodec/pngenc.c
index 630b8e35972..947c7e147b9 100644
--- a/libavcodec/pngenc.c
+++ b/libavcodec/pngenc.c
@@ -235,7 +235,7 @@ static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
     PNGEncContext *s = avctx->priv_data;
     AVFrame * const p= &s->picture;
     int bit_depth, color_type, y, len, row_size, ret, is_progressive;
-    int bits_per_pixel, pass_row_size, max_packet_size;
+    int bits_per_pixel, pass_row_size, enc_row_size, max_packet_size;
     int compression_level;
     uint8_t *ptr, *top;
     uint8_t *crow_base = NULL, *crow_buf, *crow;
@@ -247,18 +247,6 @@ static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
     p->pict_type= AV_PICTURE_TYPE_I;
     p->key_frame= 1;
 
-    max_packet_size = IOBUF_SIZE*avctx->height + FF_MIN_BUFFER_SIZE;
-    if (!pkt->data &&
-        (ret = av_new_packet(pkt, max_packet_size)) < 0) {
-        av_log(avctx, AV_LOG_ERROR, "Could not allocate output packet of size %d.\n",
-               max_packet_size);
-        return ret;
-    }
-
-    s->bytestream_start =
-    s->bytestream       = pkt->data;
-    s->bytestream_end   = pkt->data + pkt->size;
-
     is_progressive = !!(avctx->flags & CODEC_FLAG_INTERLACED_DCT);
     switch(avctx->pix_fmt) {
     case PIX_FMT_RGB32:
@@ -297,6 +285,22 @@ static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
                        Z_DEFLATED, 15, 8, Z_DEFAULT_STRATEGY);
     if (ret != Z_OK)
         return -1;
+
+    enc_row_size    = deflateBound(&s->zstream, row_size);
+    max_packet_size = avctx->height * (enc_row_size +
+                                       ((enc_row_size + IOBUF_SIZE - 1) / IOBUF_SIZE) * 12)
+                      + FF_MIN_BUFFER_SIZE;
+    if (!pkt->data &&
+        (ret = av_new_packet(pkt, max_packet_size)) < 0) {
+        av_log(avctx, AV_LOG_ERROR, "Could not allocate output packet of size %d.\n",
+               max_packet_size);
+        return ret;
+    }
+
+    s->bytestream_start =
+    s->bytestream       = pkt->data;
+    s->bytestream_end   = pkt->data + pkt->size;
+
     crow_base = av_malloc((row_size + 32) << (s->filter_type == PNG_FILTER_VALUE_MIXED));
     if (!crow_base)
         goto fail;
@@ -456,6 +460,9 @@ AVCodec ff_png_encoder = {
     .priv_data_size = sizeof(PNGEncContext),
     .init           = png_enc_init,
     .encode2        = encode_frame,
-    .pix_fmts= (const enum PixelFormat[]){PIX_FMT_RGB24, PIX_FMT_RGB32, PIX_FMT_PAL8, PIX_FMT_GRAY8, PIX_FMT_MONOBLACK, PIX_FMT_NONE},
-    .long_name= NULL_IF_CONFIG_SMALL("PNG image"),
+    .pix_fmts       = (const enum PixelFormat[]){
+        PIX_FMT_RGB24, PIX_FMT_RGB32, PIX_FMT_PAL8, PIX_FMT_GRAY8,
+        PIX_FMT_MONOBLACK, PIX_FMT_NONE
+    },
+    .long_name      = NULL_IF_CONFIG_SMALL("PNG (Portable Network Graphics) image"),
 };