[FFmpeg-devel] [PATCH v1 1/2] codec: vrawdepay: add decoder for RFC4175

Damien Riegel damien.riegel at savoirfairelinux.com
Thu Feb 16 19:43:36 EET 2017


Add a codec capable of decoding some formats of the RFC4175. For now
it's only capable of handling YCbCr-4:2:2 with 8-bit or 10-bit depth.

For 8-bit it's a simple pass-through, for 10-bit it depacks the stream
in the AV_PIX_FMT_YUV422P10 pixel format.
Change-Id: Id2184a6cee7031edbcb65a39a369623114c1783c

Signed-off-by: Damien Riegel <damien.riegel at savoirfairelinux.com>
---
 libavcodec/Makefile     |   1 +
 libavcodec/allcodecs.c  |   1 +
 libavcodec/avcodec.h    |   1 +
 libavcodec/codec_desc.c |   7 +++
 libavcodec/vrawdepay.c  | 113 ++++++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 123 insertions(+)
 create mode 100644 libavcodec/vrawdepay.c

diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index a1ce264f25..e09dcc3c1b 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -614,6 +614,7 @@ OBJS-$(CONFIG_VP9_CUVID_DECODER)       += cuvid.o
 OBJS-$(CONFIG_VP9_MEDIACODEC_DECODER)  += mediacodecdec.o
 OBJS-$(CONFIG_VPLAYER_DECODER)         += textdec.o ass.o
 OBJS-$(CONFIG_VQA_DECODER)             += vqavideo.o
+OBJS-$(CONFIG_VRAWDEPAY_DECODER)       += vrawdepay.o
 OBJS-$(CONFIG_WAVPACK_DECODER)         += wavpack.o
 OBJS-$(CONFIG_WAVPACK_ENCODER)         += wavpackenc.o
 OBJS-$(CONFIG_WEBP_DECODER)            += webp.o
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index f12a54df50..dcce291ba2 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -365,6 +365,7 @@ void avcodec_register_all(void)
     REGISTER_DECODER(VP8,               vp8);
     REGISTER_DECODER(VP9,               vp9);
     REGISTER_DECODER(VQA,               vqa);
+    REGISTER_DECODER(VRAWDEPAY,         vrawdepay);
     REGISTER_DECODER(WEBP,              webp);
     REGISTER_ENCODER(WRAPPED_AVFRAME,   wrapped_avframe);
     REGISTER_ENCDEC (WMV1,              wmv1);
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 5616fb01d6..aca4fe61e6 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -415,6 +415,7 @@ enum AVCodecID {
     AV_CODEC_ID_PIXLET,
     AV_CODEC_ID_SPEEDHQ,
     AV_CODEC_ID_FMVC,
+    AV_CODEC_ID_VRAWDEPAY,
 
     /* various PCM "codecs" */
     AV_CODEC_ID_FIRST_AUDIO = 0x10000,     ///< A dummy id pointing at the start of audio codecs
diff --git a/libavcodec/codec_desc.c b/libavcodec/codec_desc.c
index 35846c054e..8a3492adcf 100644
--- a/libavcodec/codec_desc.c
+++ b/libavcodec/codec_desc.c
@@ -1360,6 +1360,13 @@ static const AVCodecDescriptor codec_descriptors[] = {
         .long_name = NULL_IF_CONFIG_SMALL("FM Screen Capture Codec"),
         .props     = AV_CODEC_PROP_LOSSLESS,
     },
+    {
+        .id        = AV_CODEC_ID_VRAWDEPAY,
+        .type      = AVMEDIA_TYPE_VIDEO,
+        .name      = "rfc4175",
+        .long_name = NULL_IF_CONFIG_SMALL("RFC4175 video depayloader"),
+        .props     = AV_CODEC_PROP_INTRA_ONLY | AV_CODEC_PROP_LOSSLESS,
+    },
 
     /* image codecs */
     {
diff --git a/libavcodec/vrawdepay.c b/libavcodec/vrawdepay.c
new file mode 100644
index 0000000000..53a5c38bb3
--- /dev/null
+++ b/libavcodec/vrawdepay.c
@@ -0,0 +1,113 @@
+/*
+ * Raw Video Depayloader (RFC4175)
+ * Copyright (c) 2017 Savoir-faire Linux, Inc
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/* Development sponsored by CBC/Radio-Canada */
+
+/**
+ * @file
+ * Raw Video Depayloader (RFC4175)
+ */
+
+#include <libavutil/imgutils.h>
+#include "avcodec.h"
+#include "internal.h"
+#include "get_bits.h"
+
+static av_cold int vrawdepay_init_decoder(AVCodecContext *avctx)
+{
+   if (!avctx->codec_tag || !avctx->width || !avctx->height)
+      return -1;
+
+   if (avctx->codec_tag == MKTAG('U', 'Y', 'V', 'Y')) {
+      if (avctx->bits_per_coded_sample == 16)
+         avctx->pix_fmt = AV_PIX_FMT_UYVY422;
+      else if (avctx->bits_per_coded_sample == 20)
+         avctx->pix_fmt = AV_PIX_FMT_YUV422P10;
+      else
+         return -1;
+   } else {
+      return -1;
+   }
+
+    return 0;
+}
+
+static av_cold int vrawdepay_close_decoder(AVCodecContext *avctx)
+{
+   return 0;
+}
+
+static int vrawdepay_decode(AVCodecContext *avctx, void *data, int *got_frame,
+                      AVPacket *avpkt)
+{
+   const uint8_t *buf = avpkt->data;
+   int buf_size = avpkt->size;
+   AVFrame *frame = data;
+   int res;
+
+   frame->pict_type = AV_PICTURE_TYPE_I;
+   frame->key_frame = 1;
+
+   if (avctx->bits_per_coded_sample == 16) {
+      /* there is no need to copy as the data already match
+       * a known pixel format */
+      frame->buf[0] = av_buffer_ref(avpkt->buf);
+
+      if ((res = av_image_fill_arrays(frame->data, frame->linesize, buf,
+                  avctx->pix_fmt, avctx->width, avctx->height, 1)) < 0) {
+         av_buffer_unref(&frame->buf[0]);
+         return res;
+      }
+   } else {
+      GetBitContext bc;
+      uint16_t *y, *u, *v;
+      int i;
+
+      res = ff_get_buffer(avctx, frame, 0);
+      if (res < 0)
+         return res;
+      y = (uint16_t*)frame->data[0];
+      u = (uint16_t*)frame->data[1];
+      v = (uint16_t*)frame->data[2];
+
+      res = init_get_bits(&bc, buf, avctx->width * avctx->height * 20);
+      for (i = 0; i < (avctx->width * avctx->height) / 2; i++) {
+         *u++ = get_bits(&bc, 10);
+         *y++ = get_bits(&bc, 10);
+         *v++ = get_bits(&bc, 10);
+         *y++ = get_bits(&bc, 10);
+      }
+   }
+
+   *got_frame = 1;
+   return buf_size;
+
+}
+
+AVCodec ff_vrawdepay_decoder = {
+    .name   = "vrawdepay",
+    .long_name = NULL_IF_CONFIG_SMALL("RFC4175 codec"),
+    .type = AVMEDIA_TYPE_VIDEO,
+    .id = AV_CODEC_ID_VRAWDEPAY,
+    .init = vrawdepay_init_decoder,
+    .close = vrawdepay_close_decoder,
+    .decode = vrawdepay_decode,
+};
-- 
2.11.1



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