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-rw-r--r-- | third_party/aom/examples/scalable_decoder.c | 184 |
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diff --git a/third_party/aom/examples/scalable_decoder.c b/third_party/aom/examples/scalable_decoder.c new file mode 100644 index 0000000000..00fe820fd5 --- /dev/null +++ b/third_party/aom/examples/scalable_decoder.c @@ -0,0 +1,184 @@ +/* + * Copyright (c) 2018, Alliance for Open Media. All rights reserved + * + * This source code is subject to the terms of the BSD 2 Clause License and + * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License + * was not distributed with this source code in the LICENSE file, you can + * obtain it at www.aomedia.org/license/software. If the Alliance for Open + * Media Patent License 1.0 was not distributed with this source code in the + * PATENTS file, you can obtain it at www.aomedia.org/license/patent. + */ + +// Scalable Decoder +// ============== +// +// This is an example of a scalable decoder loop. It takes a 2-spatial-layer +// input file +// containing the compressed data (in OBU format), passes it through the +// decoder, and writes the decompressed frames to disk. The base layer and +// enhancement layers are stored as separate files, out_lyr0.yuv and +// out_lyr1.yuv, respectively. +// +// Standard Includes +// ----------------- +// For decoders, you only have to include `aom_decoder.h` and then any +// header files for the specific codecs you use. In this case, we're using +// av1. +// +// Initializing The Codec +// ---------------------- +// The libaom decoder is initialized by the call to aom_codec_dec_init(). +// Determining the codec interface to use is handled by AvxVideoReader and the +// functions prefixed with aom_video_reader_. Discussion of those functions is +// beyond the scope of this example, but the main gist is to open the input file +// and parse just enough of it to determine if it's a AVx file and which AVx +// codec is contained within the file. +// Note the NULL pointer passed to aom_codec_dec_init(). We do that in this +// example because we want the algorithm to determine the stream configuration +// (width/height) and allocate memory automatically. +// +// Decoding A Frame +// ---------------- +// Once the frame has been read into memory, it is decoded using the +// `aom_codec_decode` function. The call takes a pointer to the data +// (`frame`) and the length of the data (`frame_size`). No application data +// is associated with the frame in this example, so the `user_priv` +// parameter is NULL. The `deadline` parameter is left at zero for this +// example. This parameter is generally only used when doing adaptive post +// processing. +// +// Codecs may produce a variable number of output frames for every call to +// `aom_codec_decode`. These frames are retrieved by the +// `aom_codec_get_frame` iterator function. The iterator variable `iter` is +// initialized to NULL each time `aom_codec_decode` is called. +// `aom_codec_get_frame` is called in a loop, returning a pointer to a +// decoded image or NULL to indicate the end of list. +// +// Processing The Decoded Data +// --------------------------- +// In this example, we simply write the encoded data to disk. It is +// important to honor the image's `stride` values. +// +// Cleanup +// ------- +// The `aom_codec_destroy` call frees any memory allocated by the codec. +// +// Error Handling +// -------------- +// This example does not special case any error return codes. If there was +// an error, a descriptive message is printed and the program exits. With +// few exceptions, aom_codec functions return an enumerated error status, +// with the value `0` indicating success. + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "aom/aom_decoder.h" +#include "aom/aomdx.h" +#include "common/obudec.h" +#include "common/tools_common.h" +#include "common/video_reader.h" + +static const char *exec_name; + +#define MAX_LAYERS 5 + +void usage_exit(void) { + fprintf(stderr, "Usage: %s <infile>\n", exec_name); + exit(EXIT_FAILURE); +} + +int main(int argc, char **argv) { + int frame_cnt = 0; + FILE *outfile[MAX_LAYERS]; + char filename[80]; + FILE *inputfile = NULL; + uint8_t *buf = NULL; + size_t bytes_in_buffer = 0; + size_t buffer_size = 0; + struct AvxInputContext aom_input_ctx; + struct ObuDecInputContext obu_ctx = { &aom_input_ctx, NULL, 0, 0, 0 }; + aom_codec_stream_info_t si; + uint8_t tmpbuf[32]; + unsigned int i; + + exec_name = argv[0]; + + if (argc != 2) die("Invalid number of arguments."); + + if (!(inputfile = fopen(argv[1], "rb"))) + die("Failed to open %s for read.", argv[1]); + obu_ctx.avx_ctx->file = inputfile; + obu_ctx.avx_ctx->filename = argv[1]; + + aom_codec_iface_t *decoder = get_aom_decoder_by_index(0); + printf("Using %s\n", aom_codec_iface_name(decoder)); + + aom_codec_ctx_t codec; + if (aom_codec_dec_init(&codec, decoder, NULL, 0)) + die("Failed to initialize decoder."); + + if (aom_codec_control(&codec, AV1D_SET_OUTPUT_ALL_LAYERS, 1)) { + die_codec(&codec, "Failed to set output_all_layers control."); + } + + // peak sequence header OBU to get number of spatial layers + const size_t ret = fread(tmpbuf, 1, 32, inputfile); + if (ret != 32) die_codec(&codec, "Input is not a valid obu file"); + si.is_annexb = 0; + if (aom_codec_peek_stream_info(decoder, tmpbuf, 32, &si)) { + die_codec(&codec, "Input is not a valid obu file"); + } + fseek(inputfile, -32, SEEK_CUR); + + if (!file_is_obu(&obu_ctx)) + die_codec(&codec, "Input is not a valid obu file"); + + // open base layer output yuv file + snprintf(filename, sizeof(filename), "out_lyr%d.yuv", 0); + if (!(outfile[0] = fopen(filename, "wb"))) + die("Failed top open output for writing."); + + // open any enhancement layer output yuv files + for (i = 1; i < si.number_spatial_layers; i++) { + snprintf(filename, sizeof(filename), "out_lyr%u.yuv", i); + if (!(outfile[i] = fopen(filename, "wb"))) + die("Failed to open output for writing."); + } + + while (!obudec_read_temporal_unit(&obu_ctx, &buf, &bytes_in_buffer, + &buffer_size)) { + aom_codec_iter_t iter = NULL; + aom_image_t *img = NULL; + if (aom_codec_decode(&codec, buf, bytes_in_buffer, NULL)) + die_codec(&codec, "Failed to decode frame."); + + while ((img = aom_codec_get_frame(&codec, &iter)) != NULL) { + aom_image_t *img_shifted = + aom_img_alloc(NULL, AOM_IMG_FMT_I420, img->d_w, img->d_h, 16); + img_shifted->bit_depth = 8; + aom_img_downshift(img_shifted, img, + img->bit_depth - img_shifted->bit_depth); + if (img->spatial_id == 0) { + printf("Writing base layer 0 %d\n", frame_cnt); + aom_img_write(img_shifted, outfile[0]); + } else if (img->spatial_id <= (int)(si.number_spatial_layers - 1)) { + printf("Writing enhancement layer %d %d\n", img->spatial_id, frame_cnt); + aom_img_write(img_shifted, outfile[img->spatial_id]); + } else { + die_codec(&codec, "Invalid bitstream. Layer id exceeds layer count"); + } + if (img->spatial_id == (int)(si.number_spatial_layers - 1)) ++frame_cnt; + } + } + + printf("Processed %d frames.\n", frame_cnt); + if (aom_codec_destroy(&codec)) die_codec(&codec, "Failed to destroy codec"); + + for (i = 0; i < si.number_spatial_layers; i++) fclose(outfile[i]); + + fclose(inputfile); + + return EXIT_SUCCESS; +} |