lavc: add hevc mediacodec decoder

1 files changed, 134 insertions, 0 deletions

diff --git a/libavcodec/hevc_parse.c b/libavcodec/hevc_parse.c
new file mode 100644
index 0000000000..cf04bc2fff
--- /dev/null
+++ b/libavcodec/hevc_parse.c
@@ -0,0 +1,134 @@
+/*
+ * 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 "bytestream.h"
+#include "h2645_parse.h"
+#include "hevc.h"
+#include "hevc_parse.h"
+
+static int hevc_decode_nal_units(const uint8_t *buf, int buf_size, HEVCParamSets *ps,
+                                 int is_nalff, int nal_length_size, void *logctx)
+{
+    int i;
+    int ret = 0;
+    H2645Packet pkt = { 0 };
+
+    ret = ff_h2645_packet_split(&pkt, buf, buf_size, logctx, is_nalff, nal_length_size, AV_CODEC_ID_HEVC, 1);
+    if (ret < 0) {
+        goto done;
+    }
+
+    for (i = 0; i < pkt.nb_nals; i++) {
+        H2645NAL *nal = &pkt.nals[i];
+
+        /* ignore everything except parameter sets and VCL NALUs */
+        switch (nal->type) {
+        case NAL_VPS: ff_hevc_decode_nal_vps(&nal->gb, logctx, ps);    break;
+        case NAL_SPS: ff_hevc_decode_nal_sps(&nal->gb, logctx, ps, 1); break;
+        case NAL_PPS: ff_hevc_decode_nal_pps(&nal->gb, logctx, ps);    break;
+        case NAL_TRAIL_R:
+        case NAL_TRAIL_N:
+        case NAL_TSA_N:
+        case NAL_TSA_R:
+        case NAL_STSA_N:
+        case NAL_STSA_R:
+        case NAL_BLA_W_LP:
+        case NAL_BLA_W_RADL:
+        case NAL_BLA_N_LP:
+        case NAL_IDR_W_RADL:
+        case NAL_IDR_N_LP:
+        case NAL_CRA_NUT:
+        case NAL_RADL_N:
+        case NAL_RADL_R:
+        case NAL_RASL_N:
+        case NAL_RASL_R:
+            av_log(logctx, AV_LOG_ERROR, "Invalid NAL unit: %d\n", nal->type);
+            ret = AVERROR_INVALIDDATA;
+            goto done;
+            break;
+        }
+    }
+
+done:
+    ff_h2645_packet_uninit(&pkt);
+    return ret;
+}
+
+int ff_hevc_decode_extradata(const uint8_t *data, int size, HEVCParamSets *ps,
+                             int *is_nalff, int *nal_length_size,
+                             int err_recognition, void *logctx)
+{
+    int ret = 0;
+    GetByteContext gb;
+
+    bytestream2_init(&gb, data, size);
+
+    if (size > 3 && (data[0] || data[1] || data[2] > 1)) {
+        /* It seems the extradata is encoded as hvcC format.
+         * Temporarily, we support configurationVersion==0 until 14496-15 3rd
+         * is finalized. When finalized, configurationVersion will be 1 and we
+         * can recognize hvcC by checking if avctx->extradata[0]==1 or not. */
+        int i, j, num_arrays, nal_len_size;
+
+        *is_nalff = 1;
+
+        bytestream2_skip(&gb, 21);
+        nal_len_size = (bytestream2_get_byte(&gb) & 3) + 1;
+        num_arrays   = bytestream2_get_byte(&gb);
+
+        /* nal units in the hvcC always have length coded with 2 bytes,
+         * so put a fake nal_length_size = 2 while parsing them */
+        *nal_length_size = 2;
+
+        /* Decode nal units from hvcC. */
+        for (i = 0; i < num_arrays; i++) {
+            int type = bytestream2_get_byte(&gb) & 0x3f;
+            int cnt  = bytestream2_get_be16(&gb);
+
+            for (j = 0; j < cnt; j++) {
+                // +2 for the nal size field
+                int nalsize = bytestream2_peek_be16(&gb) + 2;
+                if (bytestream2_get_bytes_left(&gb) < nalsize) {
+                    av_log(logctx, AV_LOG_ERROR,
+                           "Invalid NAL unit size in extradata.\n");
+                    return AVERROR_INVALIDDATA;
+                }
+
+                ret = hevc_decode_nal_units(gb.buffer, nalsize, ps, *is_nalff, *nal_length_size, logctx);
+                if (ret < 0) {
+                    av_log(logctx, AV_LOG_ERROR,
+                           "Decoding nal unit %d %d from hvcC failed\n",
+                           type, i);
+                    return ret;
+                }
+                bytestream2_skip(&gb, nalsize);
+            }
+        }
+
+        /* Now store right nal length size, that will be used to parse
+         * all other nals */
+        *nal_length_size = nal_len_size;
+    } else {
+        *is_nalff = 0;
+        ret = hevc_decode_nal_units(data, size, ps, *is_nalff, *nal_length_size, logctx);
+        if (ret < 0)
+            return ret;
+    }
+
+    return ret;
+}