y41p encoder and decoder

y41p is a packed 12-bit 4:1:1 YUV format used by Brooktree.

Fixes issue 1123 / ticket #102.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

1 files changed, 101 insertions, 0 deletions

diff --git a/libavcodec/y41penc.c b/libavcodec/y41penc.c
new file mode 100644
index 0000000000..b8b4a2e43b
--- /dev/null
+++ b/libavcodec/y41penc.c
@@ -0,0 +1,101 @@
+/*
+ * y41p encoder
+ *
+ * Copyright (c) 2012 Paul B Mahol
+ *
+ * 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
+ */
+
+#include "avcodec.h"
+
+static av_cold int y41p_encode_init(AVCodecContext *avctx)
+{
+    if (avctx->width & 7) {
+        av_log(avctx, AV_LOG_ERROR, "y41p requires width to be divisible by 8.\n");
+        return AVERROR_INVALIDDATA;
+    }
+
+    avctx->coded_frame = avcodec_alloc_frame();
+
+    if (!avctx->coded_frame) {
+        av_log(avctx, AV_LOG_ERROR, "Could not allocate frame.\n");
+        return AVERROR(ENOMEM);
+    }
+
+    return 0;
+}
+
+static int y41p_encode_frame(AVCodecContext *avctx, uint8_t *buf,
+                             int buf_size, void *data)
+{
+    AVFrame *pic = data;
+    uint8_t *dst = buf;
+    uint8_t *y, *u, *v;
+    int i, j;
+
+    if (buf_size < avctx->width * avctx->height * 1.5) {
+        av_log(avctx, AV_LOG_ERROR, "Out buffer is too small.\n");
+        return AVERROR(ENOMEM);
+    }
+
+    avctx->coded_frame->reference = 0;
+    avctx->coded_frame->key_frame = 1;
+    avctx->coded_frame->pict_type = FF_I_TYPE;
+
+    for (i = avctx->height - 1; i >= 0; i--) {
+        y = &pic->data[0][i * pic->linesize[0]];
+        u = &pic->data[1][i * pic->linesize[1]];
+        v = &pic->data[2][i * pic->linesize[2]];
+        for (j = 0; j < avctx->width; j += 8) {
+            *(dst++) = *(u++);
+            *(dst++) = *(y++);
+            *(dst++) = *(v++);
+            *(dst++) = *(y++);
+
+            *(dst++) = *(u++);
+            *(dst++) = *(y++);
+            *(dst++) = *(v++);
+            *(dst++) = *(y++);
+
+            *(dst++) = *(y++);
+            *(dst++) = *(y++);
+            *(dst++) = *(y++);
+            *(dst++) = *(y++);
+        }
+    }
+
+    return avctx->width * avctx->height * 1.5;
+}
+
+static av_cold int y41p_encode_close(AVCodecContext *avctx)
+{
+    av_freep(&avctx->coded_frame);
+
+    return 0;
+}
+
+AVCodec ff_y41p_encoder = {
+    .name         = "y41p",
+    .type         = AVMEDIA_TYPE_VIDEO,
+    .id           = CODEC_ID_Y41P,
+    .init         = y41p_encode_init,
+    .encode       = y41p_encode_frame,
+    .close        = y41p_encode_close,
+    .pix_fmts     = (const enum PixelFormat[]) { PIX_FMT_YUV411P,
+                                                 PIX_FMT_NONE },
+    .long_name    = NULL_IF_CONFIG_SMALL("Uncompressed YUV 4:1:1 12-bit"),
+};