avformat/evc_demuxer: Added demuxer to handle reading EVC video files

- Provided AVInputFormat struct describing EVC input format (ff_evc_demuxer)

Signed-off-by: Dawid Kozinski <d.kozinski@samsung.com>

3 files changed, 174 insertions, 2 deletions

diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index a28919992a..0ce8fe5b9c 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -1258,6 +1258,7 @@ OBJS-$(CONFIG_VP9_METADATA_BSF)           += vp9_metadata_bsf.o
 OBJS-$(CONFIG_VP9_RAW_REORDER_BSF)        += vp9_raw_reorder_bsf.o
 OBJS-$(CONFIG_VP9_SUPERFRAME_BSF)         += vp9_superframe_bsf.o
 OBJS-$(CONFIG_VP9_SUPERFRAME_SPLIT_BSF)   += vp9_superframe_split_bsf.o
+OBJS-$(CONFIG_EVC_FRAME_MERGE_BSF)        += evc_frame_merge_bsf.o
 
 # thread libraries
 OBJS-$(HAVE_LIBC_MSVCRT)               += file_open.o
diff --git a/libavcodec/bitstream_filters.c b/libavcodec/bitstream_filters.c
index e8216819ca..7512fccc78 100644
--- a/libavcodec/bitstream_filters.c
+++ b/libavcodec/bitstream_filters.c
@@ -65,16 +65,17 @@ extern const FFBitStreamFilter ff_vp9_metadata_bsf;
 extern const FFBitStreamFilter ff_vp9_raw_reorder_bsf;
 extern const FFBitStreamFilter ff_vp9_superframe_bsf;
 extern const FFBitStreamFilter ff_vp9_superframe_split_bsf;
+extern const FFBitStreamFilter ff_evc_frame_merge_bsf;
 
 #include "libavcodec/bsf_list.c"
 
 const AVBitStreamFilter *av_bsf_iterate(void **opaque)
 {
-    uintptr_t i = (uintptr_t)*opaque;
+    uintptr_t i = (uintptr_t) * opaque;
     const FFBitStreamFilter *f = bitstream_filters[i];
 
     if (f) {
-        *opaque = (void*)(i + 1);
+        *opaque = (void *)(i + 1);
         return &f->p;
     }
     return NULL;
diff --git a/libavcodec/evc_frame_merge_bsf.c b/libavcodec/evc_frame_merge_bsf.c
new file mode 100644
index 0000000000..d2746a1ef6
--- /dev/null
+++ b/libavcodec/evc_frame_merge_bsf.c
@@ -0,0 +1,170 @@
+/*
+ * Copyright (c) 2019 James Almer <jamrial@gmail.com>
+ *
+ * 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 "get_bits.h"
+#include "golomb.h"
+#include "bsf.h"
+#include "bsf_internal.h"
+#include "avcodec.h"
+
+#include "evc.h"
+#include "evc_parse.h"
+
+#define INIT_AU_BUF_CAPACITY 1024
+
+// Access unit data
+typedef struct AccessUnitBuffer {
+    uint8_t *data;      // the data buffer
+    size_t data_size;   // size of data in bytes
+    size_t capacity;    // buffer capacity
+} AccessUnitBuffer;
+
+typedef struct EVCFMergeContext {
+    AVPacket *in;
+    EVCParserContext parser_ctx;
+    AccessUnitBuffer au_buffer;
+} EVCFMergeContext;
+
+static int end_of_access_unit_found(EVCParserContext *parser_ctx)
+{
+    if (parser_ctx->profile == 0) { // BASELINE profile
+        if (parser_ctx->nalu_type == EVC_NOIDR_NUT || parser_ctx->nalu_type == EVC_IDR_NUT)
+            return 1;
+    } else { // MAIN profile
+        if (parser_ctx->nalu_type == EVC_NOIDR_NUT) {
+            if (parser_ctx->poc.PicOrderCntVal != parser_ctx->poc.prevPicOrderCntVal)
+                return 1;
+        } else if (parser_ctx->nalu_type == EVC_IDR_NUT)
+            return 1;
+    }
+    return 0;
+}
+
+static void evc_frame_merge_flush(AVBSFContext *bsf)
+{
+    EVCFMergeContext *ctx = bsf->priv_data;
+
+    av_packet_unref(ctx->in);
+}
+
+static int evc_frame_merge_filter(AVBSFContext *bsf, AVPacket *out)
+{
+    EVCFMergeContext *ctx = bsf->priv_data;
+    EVCParserContext *parser_ctx = &ctx->parser_ctx;
+
+    AVPacket *in = ctx->in;
+
+    int free_space = 0;
+    size_t  nalu_size = 0;
+    uint8_t *nalu = NULL;
+    int au_end_found = 0;
+    int err;
+
+    err = ff_bsf_get_packet_ref(bsf, in);
+    if (err < 0)
+        return err;
+
+    nalu_size = evc_read_nal_unit_length(in->data, EVC_NALU_LENGTH_PREFIX_SIZE, bsf);
+    if (nalu_size <= 0) {
+        av_packet_unref(in);
+        return AVERROR_INVALIDDATA;
+    }
+
+    nalu = in->data + EVC_NALU_LENGTH_PREFIX_SIZE;
+    nalu_size = in->size - EVC_NALU_LENGTH_PREFIX_SIZE;
+
+    // NAL unit parsing needed to determine if end of AU was found
+    err = ff_evc_parse_nal_unit(parser_ctx, nalu, nalu_size, bsf);
+    if (err < 0) {
+        av_log(bsf, AV_LOG_ERROR, "NAL Unit parsing error\n");
+        av_packet_unref(in);
+
+        return err;
+    }
+
+    au_end_found = end_of_access_unit_found(parser_ctx);
+
+    free_space = ctx->au_buffer.capacity - ctx->au_buffer.data_size;
+    while (free_space < in->size) {
+        ctx->au_buffer.capacity *= 2;
+        free_space = ctx->au_buffer.capacity - ctx->au_buffer.data_size;
+
+        if (free_space >= in->size)
+            ctx->au_buffer.data = av_realloc(ctx->au_buffer.data, ctx->au_buffer.capacity);
+    }
+
+    memcpy(ctx->au_buffer.data + ctx->au_buffer.data_size, in->data, in->size);
+
+    ctx->au_buffer.data_size += in->size;
+
+    av_packet_unref(in);
+
+    if (au_end_found) {
+        uint8_t *data = av_memdup(ctx->au_buffer.data, ctx->au_buffer.data_size);
+        err = av_packet_from_data(out, data, ctx->au_buffer.data_size);
+
+        ctx->au_buffer.data_size = 0;
+    } else
+        err = AVERROR(EAGAIN);
+
+    if (err < 0 && err != AVERROR(EAGAIN))
+        evc_frame_merge_flush(bsf);
+
+    return err;
+}
+
+static int evc_frame_merge_init(AVBSFContext *bsf)
+{
+    EVCFMergeContext *ctx = bsf->priv_data;
+
+    ctx->in  = av_packet_alloc();
+    if (!ctx->in)
+        return AVERROR(ENOMEM);
+
+    ctx->au_buffer.capacity = INIT_AU_BUF_CAPACITY;
+    ctx->au_buffer.data = av_malloc(INIT_AU_BUF_CAPACITY);
+    ctx->au_buffer.data_size = 0;
+
+    return 0;
+}
+
+static void evc_frame_merge_close(AVBSFContext *bsf)
+{
+    EVCFMergeContext *ctx = bsf->priv_data;
+
+    av_packet_free(&ctx->in);
+
+    ctx->au_buffer.capacity = 0;
+    av_freep(&ctx->au_buffer.data);
+    ctx->au_buffer.data_size = 0;
+}
+
+static const enum AVCodecID evc_frame_merge_codec_ids[] = {
+    AV_CODEC_ID_EVC, AV_CODEC_ID_NONE,
+};
+
+const FFBitStreamFilter ff_evc_frame_merge_bsf = {
+    .p.name         = "evc_frame_merge",
+    .p.codec_ids    = evc_frame_merge_codec_ids,
+    .priv_data_size = sizeof(EVCFMergeContext),
+    .init           = evc_frame_merge_init,
+    .flush          = evc_frame_merge_flush,
+    .close          = evc_frame_merge_close,
+    .filter         = evc_frame_merge_filter,
+};