[FFmpeg-devel] [PATCH 4/5] apng: Make PNG encoder only write headers once in APNG mode

[Donny Yang]

Signed-off-by: Donny Yang <work at kota.moe>
---
 configure              |  1 +
 libavcodec/Makefile    |  1 +
 libavcodec/allcodecs.c |  2 +-
 libavcodec/pngenc.c    | 40 ++++++++++++++++++++++++++++++++++++----
 libavcodec/version.h   |  2 +-
 5 files changed, 40 insertions(+), 6 deletions(-)

diff --git a/configure b/configure
index 017a9d2..8a30549 100755
--- a/configure
+++ b/configure
@@ -2096,6 +2096,7 @@ amv_decoder_select="sp5x_decoder exif"
 amv_encoder_select="aandcttables mpegvideoenc"
 ape_decoder_select="bswapdsp llauddsp"
 apng_decoder_select="zlib"
+apng_encoder_select="huffyuvencdsp zlib"
 asv1_decoder_select="blockdsp bswapdsp idctdsp"
 asv1_encoder_select="bswapdsp fdctdsp pixblockdsp"
 asv2_decoder_select="blockdsp bswapdsp idctdsp"
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index b2d9c71..9a145d3 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -144,6 +144,7 @@ OBJS-$(CONFIG_ANM_DECODER)             += anm.o
 OBJS-$(CONFIG_ANSI_DECODER)            += ansi.o cga_data.o
 OBJS-$(CONFIG_APE_DECODER)             += apedec.o
 OBJS-$(CONFIG_APNG_DECODER)            += png.o pngdec.o pngdsp.o
+OBJS-$(CONFIG_APNG_ENCODER)            += png.o pngenc.o
 OBJS-$(CONFIG_SSA_DECODER)             += assdec.o ass.o ass_split.o
 OBJS-$(CONFIG_SSA_ENCODER)             += assenc.o ass.o
 OBJS-$(CONFIG_ASS_DECODER)             += assdec.o ass.o ass_split.o
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index 10aad4c..2e5d558 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -107,7 +107,7 @@ void avcodec_register_all(void)
     REGISTER_ENCDEC (AMV,               amv);
     REGISTER_DECODER(ANM,               anm);
     REGISTER_DECODER(ANSI,              ansi);
-    REGISTER_DECODER(APNG,              apng);
+    REGISTER_ENCDEC (APNG,              apng);
     REGISTER_ENCDEC (ASV1,              asv1);
     REGISTER_ENCDEC (ASV2,              asv2);
     REGISTER_DECODER(AURA,              aura);
diff --git a/libavcodec/pngenc.c b/libavcodec/pngenc.c
index 0264575..6959435 100644
--- a/libavcodec/pngenc.c
+++ b/libavcodec/pngenc.c
@@ -485,15 +485,19 @@ static int encode(AVCodecContext *avctx, AVPacket *pkt,
     s->bytestream       = pkt->data;
     s->bytestream_end   = pkt->data + pkt->size;
 
-    ret = encode_headers(avctx, pict);
-    if (ret)
-        return ret;
+    if (avctx->codec_id == AV_CODEC_ID_PNG || pict->pts == 0) {
+        ret = encode_headers(avctx, pict);
+        if (ret)
+            return ret;
+    }
 
     ret = encode_frame(avctx, pict);
     if (ret)
         return ret;
 
-    png_write_chunk(&s->bytestream, MKTAG('I', 'E', 'N', 'D'), NULL, 0);
+    if (avctx->codec_id == AV_CODEC_ID_PNG) {
+        png_write_chunk(&s->bytestream, MKTAG('I', 'E', 'N', 'D'), NULL, 0);
+    }
 
     pkt->size = s->bytestream - s->bytestream_start;
     pkt->flags |= AV_PKT_FLAG_KEY;
@@ -629,6 +633,13 @@ static const AVClass pngenc_class = {
     .version    = LIBAVUTIL_VERSION_INT,
 };
 
+static const AVClass apngenc_class = {
+    .class_name = "APNG encoder",
+    .item_name  = av_default_item_name,
+    .option     = options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
+
 AVCodec ff_png_encoder = {
     .name           = "png",
     .long_name      = NULL_IF_CONFIG_SMALL("PNG (Portable Network Graphics) image"),
@@ -649,3 +660,24 @@ AVCodec ff_png_encoder = {
     },
     .priv_class     = &pngenc_class,
 };
+
+AVCodec ff_apng_encoder = {
+    .name           = "apng",
+    .long_name      = NULL_IF_CONFIG_SMALL("APNG (Animated Portable Network Graphics) image"),
+    .type           = AVMEDIA_TYPE_VIDEO,
+    .id             = AV_CODEC_ID_APNG,
+    .priv_data_size = sizeof(PNGEncContext),
+    .init           = png_enc_init,
+    .close          = png_enc_close,
+    .encode2        = encode,
+    .capabilities   = CODEC_CAP_FRAME_THREADS | CODEC_CAP_INTRA_ONLY,
+    .pix_fmts       = (const enum AVPixelFormat[]) {
+        AV_PIX_FMT_RGB24, AV_PIX_FMT_RGBA,
+        AV_PIX_FMT_RGB48BE, AV_PIX_FMT_RGBA64BE,
+        // TODO: AV_PIX_FMT_PAL8,
+        AV_PIX_FMT_GRAY8, AV_PIX_FMT_GRAY8A,
+        AV_PIX_FMT_GRAY16BE, AV_PIX_FMT_YA16BE,
+        AV_PIX_FMT_MONOBLACK, AV_PIX_FMT_NONE
+    },
+    .priv_class     = &apngenc_class,
+};
diff --git a/libavcodec/version.h b/libavcodec/version.h
index 5a93c68..a351b08 100644
--- a/libavcodec/version.h
+++ b/libavcodec/version.h
@@ -29,7 +29,7 @@
 #include "libavutil/version.h"
 
 #define LIBAVCODEC_VERSION_MAJOR 56
-#define LIBAVCODEC_VERSION_MINOR  31
+#define LIBAVCODEC_VERSION_MINOR  32
 #define LIBAVCODEC_VERSION_MICRO 100
 
 #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
-- 
2.3.4