[FFmpeg-devel] [PATCH 4/5] [IMF demuxer] Demuxer implementation
pal at sandflow.com
pal at sandflow.com
Thu Sep 23 20:00:41 EEST 2021
From: Pierre-Anthony Lemieux <pal at palemieux.com>
Signed-off-by: Pierre-Anthony Lemieux <pal at palemieux.com>
---
Notes:
Implements the IMF demuxer, which accepts as input an IMF CPL. The assets referenced by the CPL can be contained in multiple deliveries, each defined by an ASSETMAP file:./ffmpeg -assetmaps \<path of ASSETMAP1\>,\<path of ASSETMAP\>,... -i \<path of CPL\> If -assetmaps is not specified, FFMPEG looks for a file called ASSETMAP.xml in the same directory as the CPL.
libavformat/imfdec.c | 646 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 646 insertions(+)
create mode 100644 libavformat/imfdec.c
diff --git a/libavformat/imfdec.c b/libavformat/imfdec.c
new file mode 100644
index 0000000000..1dee2ba8bb
--- /dev/null
+++ b/libavformat/imfdec.c
@@ -0,0 +1,646 @@
+/*
+ * This file is part of FFmpeg.
+ *
+ * Copyright (c) Sandflow Consulting LLC
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/**
+ * Demuxes an IMF Composition
+ *
+ * References
+ * OV 2067-0:2018 - SMPTE Overview Document - Interoperable Master Format
+ * ST 2067-2:2020 - SMPTE Standard - Interoperable Master Format — Core Constraints
+ * ST 2067-3:2020 - SMPTE Standard - Interoperable Master Format — Composition Playlist
+ * ST 2067-5:2020 - SMPTE Standard - Interoperable Master Format — Essence Component
+ * ST 2067-20:2016 - SMPTE Standard - Interoperable Master Format — Application #2
+ * ST 2067-21:2020 - SMPTE Standard - Interoperable Master Format — Application #2 Extended
+ * ST 2067-102:2017 - SMPTE Standard - Interoperable Master Format — Common Image Pixel Color Schemes
+ * ST 429-9:2007 - SMPTE Standard - D-Cinema Packaging — Asset Mapping and File Segmentation
+ *
+ * @author Marc-Antoine Arnaud
+ * @author Valentin Noel
+ * @file
+ * @ingroup lavu_imf
+ */
+
+#include "imf.h"
+#include "imf_internal.h"
+#include "internal.h"
+#include "libavutil/opt.h"
+#include "libavutil/bprint.h"
+#include "libavutil/avstring.h"
+#include "mxf.h"
+#include "url.h"
+#include <libxml/parser.h>
+#include <inttypes.h>
+
+#define MAX_BPRINT_READ_SIZE (UINT_MAX - 1)
+#define DEFAULT_ASSETMAP_SIZE 8 * 1024
+
+typedef struct IMFVirtualTrackResourcePlaybackCtx {
+ IMFAssetLocator *locator;
+ IMFTrackFileResource *resource;
+ AVFormatContext *ctx;
+} IMFVirtualTrackResourcePlaybackCtx;
+
+typedef struct IMFVirtualTrackPlaybackCtx {
+ // Track index in playlist
+ int32_t index;
+ // Time counters
+ AVRational current_timestamp;
+ AVRational duration;
+ // Resources
+ unsigned int resource_count;
+ IMFVirtualTrackResourcePlaybackCtx **resources;
+ // Decoding cursors
+ uint32_t current_resource_index;
+ int64_t last_pts;
+} IMFVirtualTrackPlaybackCtx;
+
+typedef struct IMFContext {
+ const AVClass *class;
+ const char *base_url;
+ char *asset_map_paths;
+ AVIOInterruptCB *interrupt_callback;
+ AVDictionary *avio_opts;
+ IMFCPL *cpl;
+ IMFAssetLocatorMap *asset_locator_map;
+ unsigned int track_count;
+ IMFVirtualTrackPlaybackCtx **tracks;
+} IMFContext;
+
+int is_url(const char *string) {
+ char *substr = strstr(string, "://");
+ return substr != NULL;
+}
+
+int is_unix_absolute_path(const char *string) {
+ char *substr = strstr(string, "/");
+ int index = (int)(substr - string);
+ return index == 0;
+}
+
+int is_dos_absolute_path(const char *string) {
+ // Absolute path case: `C:\path\to\somwhere`
+ char *substr = strstr(string, ":\\");
+ int index = (int)(substr - string);
+ if (index == 1) {
+ return 1;
+ }
+
+ // Absolute path case: `C:/path/to/somwhere`
+ substr = strstr(string, ":/");
+ index = (int)(substr - string);
+ if (index == 1) {
+ return 1;
+ }
+
+ // Network path case: `\\path\to\somwhere`
+ substr = strstr(string, "\\\\");
+ index = (int)(substr - string);
+ return index == 0;
+}
+
+int parse_imf_asset_map_from_xml_dom(AVFormatContext *s, xmlDocPtr doc, IMFAssetLocatorMap **asset_map, const char *base_url) {
+ xmlNodePtr asset_map_element = NULL;
+ xmlNodePtr node = NULL;
+ char *uri;
+ int ret = 0;
+
+ IMFAssetLocator *asset = NULL;
+
+ asset_map_element = xmlDocGetRootElement(doc);
+
+ if (!asset_map_element) {
+ av_log(s, AV_LOG_ERROR, "Unable to parse asset map XML - missing root node\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ if (asset_map_element->type != XML_ELEMENT_NODE || av_strcasecmp(asset_map_element->name, "AssetMap")) {
+ av_log(s, AV_LOG_ERROR, "Unable to parse asset map XML - wrong root node name[%s] type[%d]\n", asset_map_element->name, (int)asset_map_element->type);
+ return AVERROR_INVALIDDATA;
+ }
+
+ // parse asset locators
+
+ if (!(node = xml_get_child_element_by_name(asset_map_element, "AssetList"))) {
+ av_log(s, AV_LOG_ERROR, "Unable to parse asset map XML - missing AssetList node\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ node = xmlFirstElementChild(node);
+ while (node) {
+ if (av_strcasecmp(node->name, "Asset") != 0) {
+ continue;
+ }
+
+ asset = av_malloc(sizeof(IMFAssetLocator));
+
+ if (xml_read_UUID(xml_get_child_element_by_name(node, "Id"), asset->uuid)) {
+ av_log(s, AV_LOG_ERROR, "Could not parse UUID from asset in asset map.\n");
+ av_freep(&asset);
+ return 1;
+ }
+
+ av_log(s, AV_LOG_DEBUG, "Found asset id: " UUID_FORMAT "\n", UID_ARG(asset->uuid));
+
+ if (!(node = xml_get_child_element_by_name(node, "ChunkList"))) {
+ av_log(s, AV_LOG_ERROR, "Unable to parse asset map XML - missing ChunkList node\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ if (!(node = xml_get_child_element_by_name(node, "Chunk"))) {
+ av_log(s, AV_LOG_ERROR, "Unable to parse asset map XML - missing Chunk node\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ uri = xmlNodeGetContent(xml_get_child_element_by_name(node, "Path"));
+
+ if (!is_url(uri) && !is_unix_absolute_path(uri) && !is_dos_absolute_path(uri)) {
+ uri = av_append_path_component(base_url, uri);
+ }
+
+ asset->absolute_uri = strdup(uri);
+ av_free(uri);
+
+ av_log(s, AV_LOG_DEBUG, "Found asset absolute URI: %s\n", asset->absolute_uri);
+
+ node = xmlNextElementSibling(node->parent->parent);
+
+ (*asset_map)->assets = av_realloc((*asset_map)->assets, ((*asset_map)->asset_count + 1) * sizeof(IMFAssetLocator));
+ (*asset_map)->assets[(*asset_map)->asset_count++] = asset;
+ }
+
+ return ret;
+}
+
+IMFAssetLocatorMap *imf_asset_locator_map_alloc(void) {
+ IMFAssetLocatorMap *asset_map;
+
+ asset_map = av_malloc(sizeof(IMFAssetLocatorMap));
+ if (!asset_map)
+ return NULL;
+
+ asset_map->assets = NULL;
+ asset_map->asset_count = 0;
+ return asset_map;
+}
+
+void imf_asset_locator_map_free(IMFAssetLocatorMap *asset_map) {
+ if (asset_map == NULL) {
+ return;
+ }
+
+ for (int i = 0; i < asset_map->asset_count; ++i) {
+ av_free(asset_map->assets[i]);
+ }
+
+ av_freep(&asset_map->assets);
+ av_freep(&asset_map);
+}
+
+static int parse_assetmap(AVFormatContext *s, const char *url, AVIOContext *in) {
+ IMFContext *c = s->priv_data;
+ struct AVBPrint buf;
+ AVDictionary *opts = NULL;
+ xmlDoc *doc = NULL;
+ const char *base_url;
+
+ int close_in = 0;
+ int ret;
+ int64_t filesize;
+
+ base_url = av_dirname(strdup(url));
+ if (c->asset_locator_map == NULL) {
+ c->asset_locator_map = imf_asset_locator_map_alloc();
+ if (!c->asset_locator_map) {
+ av_log(s, AV_LOG_ERROR, "Unable to allocate asset map locator\n");
+ return AVERROR_BUG;
+ }
+ }
+
+ av_log(s, AV_LOG_DEBUG, "Asset Map URL: %s\n", url);
+
+ if (!in) {
+ close_in = 1;
+
+ av_dict_copy(&opts, c->avio_opts, 0);
+ ret = avio_open2(&in, url, AVIO_FLAG_READ, c->interrupt_callback, &opts);
+ av_dict_free(&opts);
+ if (ret < 0)
+ return ret;
+ }
+
+ filesize = avio_size(in);
+ filesize = filesize > 0 ? filesize : DEFAULT_ASSETMAP_SIZE;
+
+ av_bprint_init(&buf, filesize + 1, AV_BPRINT_SIZE_UNLIMITED);
+
+ if ((ret = avio_read_to_bprint(in, &buf, MAX_BPRINT_READ_SIZE)) < 0 || !avio_feof(in) || (filesize = buf.len) == 0) {
+ av_log(s, AV_LOG_ERROR, "Unable to read to asset map '%s'\n", url);
+ if (ret == 0)
+ ret = AVERROR_INVALIDDATA;
+ } else {
+ LIBXML_TEST_VERSION
+
+ doc = xmlReadMemory(buf.str, filesize, url, NULL, 0);
+
+ ret = parse_imf_asset_map_from_xml_dom(s, doc, &c->asset_locator_map, base_url);
+ if (ret != 0) {
+ goto cleanup;
+ }
+
+ av_log(s, AV_LOG_DEBUG, "Found %d assets from %s\n", c->asset_locator_map->asset_count, url);
+
+ cleanup:
+ xmlFreeDoc(doc);
+ }
+ if (close_in) {
+ avio_close(in);
+ }
+ return ret;
+}
+
+static IMFAssetLocator *find_asset_map_locator(IMFAssetLocatorMap *asset_map, UUID uuid) {
+ IMFAssetLocator *asset_locator;
+ for (int i = 0; i < asset_map->asset_count; ++i) {
+ asset_locator = asset_map->assets[i];
+ if (memcmp(asset_map->assets[i]->uuid, uuid, 16) == 0) {
+ return asset_locator;
+ }
+ }
+ return NULL;
+}
+
+static int open_track_resource_context(AVFormatContext *s, IMFVirtualTrackResourcePlaybackCtx *track_resource) {
+ int ret = 0;
+ int64_t entry_point;
+
+ if (!track_resource->ctx) {
+ track_resource->ctx = avformat_alloc_context();
+ }
+
+ if (track_resource->ctx->iformat) {
+ av_log(s, AV_LOG_DEBUG, "Input context already opened for %s.\n", track_resource->locator->absolute_uri);
+ return ret;
+ }
+
+ ret = avformat_open_input(&track_resource->ctx, track_resource->locator->absolute_uri, NULL, NULL);
+ if (ret < 0) {
+ av_log(s, AV_LOG_ERROR, "Could not open %s input context: %s\n", track_resource->locator->absolute_uri, av_err2str(ret));
+ goto cleanup;
+ }
+
+ ret = avformat_find_stream_info(track_resource->ctx, NULL);
+ if (ret < 0) {
+ av_log(s, AV_LOG_ERROR, "Could not find %s stream information: %s\n", track_resource->locator->absolute_uri, av_err2str(ret));
+ goto cleanup;
+ }
+
+ // Compare the source timebase to the resource edit rate, considering the first stream of the source file
+ if (av_cmp_q(track_resource->ctx->streams[0]->time_base, av_inv_q(track_resource->resource->base.edit_rate))) {
+ av_log(s, AV_LOG_WARNING, "Incoherent source stream timebase %d/%d regarding resource edit rate: %d/%d", track_resource->ctx->streams[0]->time_base.num, track_resource->ctx->streams[0]->time_base.den, track_resource->resource->base.edit_rate.den, track_resource->resource->base.edit_rate.num);
+ }
+
+ entry_point = (int64_t)track_resource->resource->base.entry_point * track_resource->resource->base.edit_rate.den * AV_TIME_BASE / track_resource->resource->base.edit_rate.num;
+
+ if (entry_point) {
+ av_log(s, AV_LOG_DEBUG, "Seek at resource %s entry point: %ld\n", track_resource->locator->absolute_uri, track_resource->resource->base.entry_point);
+ ret = avformat_seek_file(track_resource->ctx, -1, entry_point, entry_point, entry_point, 0);
+ if (ret < 0) {
+ av_log(s, AV_LOG_ERROR, "Could not seek at %" PRId64 "on %s: %s\n", entry_point, track_resource->locator->absolute_uri, av_err2str(ret));
+ goto cleanup;
+ }
+ }
+
+ return ret;
+cleanup:
+ avformat_free_context(track_resource->ctx);
+ return ret;
+}
+
+static int open_track_file_resource(AVFormatContext *s, IMFTrackFileResource *track_file_resource, IMFVirtualTrackPlaybackCtx *track) {
+ IMFContext *c = s->priv_data;
+ IMFVirtualTrackResourcePlaybackCtx *track_resource;
+ IMFAssetLocator *asset_locator;
+
+ int ret;
+
+ if (!(asset_locator = find_asset_map_locator(c->asset_locator_map, track_file_resource->track_file_uuid))) {
+ av_log(s, AV_LOG_ERROR, "Could not find asset locator for UUID: " UUID_FORMAT "\n", UID_ARG(track_file_resource->track_file_uuid));
+ return AVERROR_INVALIDDATA;
+ }
+
+ av_log(s, AV_LOG_DEBUG, "Found locator for " UUID_FORMAT ": %s\n", UID_ARG(asset_locator->uuid), asset_locator->absolute_uri);
+
+ track_resource = av_mallocz(sizeof(IMFVirtualTrackResourcePlaybackCtx));
+ track_resource->locator = asset_locator;
+ track_resource->resource = track_file_resource;
+
+ if ((ret = open_track_resource_context(s, track_resource)) != 0) {
+ return ret;
+ }
+
+ for (int repetition = 0; repetition < track_file_resource->base.repeat_count; ++repetition) {
+ track->resources = av_realloc(track->resources, (track->resource_count + 1) * sizeof(IMFVirtualTrackResourcePlaybackCtx));
+ track->resources[track->resource_count++] = track_resource;
+ track->duration = av_add_q(track->duration, av_make_q((int)track_resource->resource->base.duration * track_resource->resource->base.edit_rate.den, track_resource->resource->base.edit_rate.num));
+ }
+
+ return ret;
+}
+
+static int open_virtual_track(AVFormatContext *s, IMFTrackFileVirtualTrack *virtual_track, int32_t track_index) {
+ IMFContext *c = s->priv_data;
+ IMFVirtualTrackPlaybackCtx *track;
+ int ret = 0;
+
+ track = av_mallocz(sizeof(IMFVirtualTrackPlaybackCtx));
+ track->index = track_index;
+ track->duration = av_make_q(0, INT32_MAX);
+
+ for (int i = 0; i < virtual_track->resource_count; i++) {
+ av_log(s, AV_LOG_DEBUG, "Open stream from file " UUID_FORMAT ", stream %d\n", UID_ARG(virtual_track->resources[i].track_file_uuid), i);
+ if ((ret = open_track_file_resource(s, &virtual_track->resources[i], track)) != 0) {
+ av_log(s, AV_LOG_ERROR, "Could not open image track resource " UUID_FORMAT "\n", UID_ARG(virtual_track->resources[i].track_file_uuid));
+ return ret;
+ }
+ }
+
+ track->current_timestamp = av_make_q(0, track->duration.den);
+
+ c->tracks = av_realloc(c->tracks, (c->track_count + 1) * sizeof(IMFVirtualTrackPlaybackCtx));
+ c->tracks[c->track_count++] = track;
+
+ return ret;
+}
+
+static void imf_virtual_track_playback_context_free(IMFVirtualTrackPlaybackCtx *track) {
+ if (!track) {
+ return;
+ }
+
+ for (int i = 0; i < track->resource_count; ++i) {
+ if (!track->resources[i]) {
+ continue;
+ }
+
+ if (track->resources[i]->ctx && track->resources[i]->ctx->iformat) {
+ avformat_free_context(track->resources[i]->ctx);
+ track->resources[i]->ctx = NULL;
+ }
+ }
+}
+
+static int set_context_streams_from_tracks(AVFormatContext *s) {
+ IMFContext *c = s->priv_data;
+
+ AVStream *asset_stream;
+ AVStream *first_resource_stream;
+
+ int ret = 0;
+
+ for (int i = 0; i < c->track_count; ++i) {
+ // Open the first resource of the track to get stream information
+ first_resource_stream = c->tracks[i]->resources[0]->ctx->streams[0];
+
+ av_log(s, AV_LOG_DEBUG, "Open the first resource of track %d\n", c->tracks[i]->index);
+
+ // Copy stream information
+ asset_stream = avformat_new_stream(s, NULL);
+ asset_stream->id = i;
+ if ((ret = avcodec_parameters_copy(asset_stream->codecpar, first_resource_stream->codecpar)) < 0) {
+ av_log(s, AV_LOG_ERROR, "Could not copy stream parameters\n");
+ break;
+ }
+ avpriv_set_pts_info(asset_stream, first_resource_stream->pts_wrap_bits, first_resource_stream->time_base.num, first_resource_stream->time_base.den);
+ asset_stream->duration = (int64_t)av_q2d(av_mul_q(c->tracks[i]->duration, av_inv_q(asset_stream->time_base)));
+ }
+
+ return ret;
+}
+
+static int open_cpl_tracks(AVFormatContext *s) {
+ IMFContext *c = s->priv_data;
+ int32_t track_index = 0;
+ int ret;
+
+ if (c->cpl->main_image_2d_track) {
+ if ((ret = open_virtual_track(s, c->cpl->main_image_2d_track, track_index++)) != 0) {
+ av_log(s, AV_LOG_ERROR, "Could not open image track " UUID_FORMAT "\n", UID_ARG(c->cpl->main_image_2d_track->base.id_uuid));
+ return ret;
+ }
+ }
+
+ for (int audio_track_index = 0; audio_track_index < c->cpl->main_audio_track_count; ++audio_track_index) {
+ if ((ret = open_virtual_track(s, &c->cpl->main_audio_tracks[audio_track_index], track_index++)) != 0) {
+ av_log(s, AV_LOG_ERROR, "Could not open audio track " UUID_FORMAT "\n", UID_ARG(c->cpl->main_audio_tracks[audio_track_index].base.id_uuid));
+ return ret;
+ }
+ }
+
+ return set_context_streams_from_tracks(s);
+}
+
+static int imf_close(AVFormatContext *s);
+
+static int imf_read_header(AVFormatContext *s) {
+ IMFContext *c = s->priv_data;
+ char *asset_map_path;
+ int ret;
+
+ c->base_url = av_dirname(av_strdup(s->url));
+
+ av_log(s, AV_LOG_DEBUG, "start parsing IMF CPL: %s\n", s->url);
+
+ if ((ret = parse_imf_cpl(s->pb, &c->cpl)) < 0)
+ goto fail;
+
+ av_log(s, AV_LOG_DEBUG, "parsed IMF CPL: " UUID_FORMAT "\n", UID_ARG(c->cpl->id_uuid));
+
+ if (!c->asset_map_paths) {
+ c->asset_map_paths = av_append_path_component(c->base_url, "ASSETMAP.xml");
+ }
+
+ // Parse each asset map XML file
+ asset_map_path = strtok(c->asset_map_paths, ",");
+ while (asset_map_path != NULL) {
+ av_log(s, AV_LOG_DEBUG, "start parsing IMF Asset Map: %s\n", asset_map_path);
+
+ if ((ret = parse_assetmap(s, asset_map_path, NULL)) < 0)
+ goto fail;
+
+ asset_map_path = strtok(NULL, ",");
+ }
+
+ av_log(s, AV_LOG_DEBUG, "parsed IMF Asset Maps\n");
+
+ if ((ret = open_cpl_tracks(s)) != 0) {
+ goto fail;
+ }
+
+ av_log(s, AV_LOG_DEBUG, "parsed IMF package\n");
+ return ret;
+
+fail:
+ imf_close(s);
+ return ret;
+}
+
+static IMFVirtualTrackPlaybackCtx *get_next_track_with_minimum_timestamp(AVFormatContext *s) {
+ IMFContext *c = s->priv_data;
+ IMFVirtualTrackPlaybackCtx *track;
+
+ AVRational minimum_timestamp = av_make_q(INT32_MAX, 1);
+ for (int i = 0; i < c->track_count; ++i) {
+ av_log(s, AV_LOG_DEBUG, "Compare track %d timestamp " AVRATIONAL_FORMAT " to minimum " AVRATIONAL_FORMAT " (over duration: " AVRATIONAL_FORMAT ")\n", i, AVRATIONAL_ARG(c->tracks[i]->current_timestamp), AVRATIONAL_ARG(minimum_timestamp), AVRATIONAL_ARG(c->tracks[i]->duration));
+ if (av_cmp_q(c->tracks[i]->current_timestamp, minimum_timestamp) < 0) {
+ track = c->tracks[i];
+ minimum_timestamp = track->current_timestamp;
+ }
+ }
+
+ av_log(s, AV_LOG_DEBUG, "Found next track to read: %d (timestamp: %lf / %lf)\n", track->index, av_q2d(track->current_timestamp), av_q2d(minimum_timestamp));
+ return track;
+}
+
+static IMFVirtualTrackResourcePlaybackCtx *get_resource_context_for_timestamp(AVFormatContext *s, IMFVirtualTrackPlaybackCtx *track) {
+ AVRational edit_unit_duration = av_inv_q(track->resources[0]->resource->base.edit_rate);
+ AVRational cumulated_duration = av_make_q(0, edit_unit_duration.den);
+
+ av_log(s, AV_LOG_DEBUG, "Looking for track %d resource for timestamp = %lf / %lf\n", track->index, av_q2d(track->current_timestamp), av_q2d(track->duration));
+ for (int i = 0; i < track->resource_count; ++i) {
+ cumulated_duration = av_add_q(cumulated_duration, av_make_q((int)track->resources[i]->resource->base.duration * edit_unit_duration.num, edit_unit_duration.den));
+
+ if (av_cmp_q(av_add_q(track->current_timestamp, edit_unit_duration), cumulated_duration) <= 0) {
+ av_log(s, AV_LOG_DEBUG, "Found resource %d in track %d to read for timestamp %lf (on cumulated=%lf): entry=%ld, duration=%lu, editrate=" AVRATIONAL_FORMAT " | edit_unit_duration=%lf\n", i, track->index, av_q2d(track->current_timestamp), av_q2d(cumulated_duration), track->resources[i]->resource->base.entry_point, track->resources[i]->resource->base.duration, AVRATIONAL_ARG(track->resources[i]->resource->base.edit_rate), av_q2d(edit_unit_duration));
+
+ if (track->current_resource_index != i) {
+ av_log(s, AV_LOG_DEBUG, "Switch resource on track %d: re-open context\n", track->index);
+ if (track->resources[track->current_resource_index] != NULL) {
+ avformat_close_input(&track->resources[track->current_resource_index]->ctx);
+ }
+ if (open_track_resource_context(s, track->resources[i]) != 0) {
+ return NULL;
+ }
+ track->current_resource_index = i;
+ }
+ return track->resources[track->current_resource_index];
+ }
+ }
+ return NULL;
+}
+
+static int ff_imf_read_packet(AVFormatContext *s, AVPacket *pkt) {
+ IMFContext *c = s->priv_data;
+
+ IMFVirtualTrackResourcePlaybackCtx *resource_to_read = NULL;
+ AVRational edit_unit_duration;
+ int ret = 0;
+
+ IMFVirtualTrackPlaybackCtx *track_to_read = get_next_track_with_minimum_timestamp(s);
+ FFStream* track_to_read_stream_internal;
+
+ if (av_cmp_q(track_to_read->current_timestamp, track_to_read->duration) == 0) {
+ return AVERROR_EOF;
+ }
+
+ resource_to_read = get_resource_context_for_timestamp(s, track_to_read);
+
+ if (!resource_to_read) {
+ edit_unit_duration = av_inv_q(track_to_read->resources[track_to_read->current_resource_index]->resource->base.edit_rate);
+ if (av_cmp_q(av_add_q(track_to_read->current_timestamp, edit_unit_duration), track_to_read->duration) > 0) {
+ return AVERROR_EOF;
+ }
+
+ av_log(s, AV_LOG_ERROR, "Could not find IMF track resource to read\n");
+ return AVERROR_STREAM_NOT_FOUND;
+ }
+
+ while (!ff_check_interrupt(c->interrupt_callback) && !ret) {
+ ret = av_read_frame(resource_to_read->ctx, pkt);
+ av_log(s, AV_LOG_DEBUG, "Got packet: pts=%" PRId64 ", dts=%" PRId64 ", duration=%" PRId64 ", stream_index=%d, pos=%" PRId64 "\n", pkt->pts, pkt->dts, pkt->duration, pkt->stream_index, pkt->pos);
+ track_to_read_stream_internal = ffstream(s->streams[track_to_read->index]);
+ if (ret >= 0) {
+ // Update packet info from track
+ if (pkt->dts < track_to_read_stream_internal->cur_dts && track_to_read->last_pts > 0) {
+ pkt->dts = track_to_read_stream_internal->cur_dts;
+ }
+
+ pkt->pts = track_to_read->last_pts;
+ pkt->dts = pkt->dts - (int64_t)track_to_read->resources[track_to_read->current_resource_index]->resource->base.entry_point;
+ pkt->stream_index = track_to_read->index;
+
+ // Update track cursors
+ track_to_read->current_timestamp = av_add_q(track_to_read->current_timestamp, av_make_q((int)pkt->duration * resource_to_read->ctx->streams[0]->time_base.num, resource_to_read->ctx->streams[0]->time_base.den));
+ track_to_read->last_pts += pkt->duration;
+
+ return 0;
+ } else if (ret != AVERROR_EOF) {
+ av_log(s, AV_LOG_ERROR, "Could not get packet from track %d: %s\n", track_to_read->index, av_err2str(ret));
+ return ret;
+ }
+ }
+
+ return AVERROR_EOF;
+}
+
+static int imf_close(AVFormatContext *s) {
+ IMFContext *c = s->priv_data;
+
+ av_log(s, AV_LOG_DEBUG, "Close IMF package\n");
+ av_dict_free(&c->avio_opts);
+ av_freep(&c->base_url);
+ imf_asset_locator_map_free(c->asset_locator_map);
+ imf_cpl_free(c->cpl);
+
+ for (int i = 0; i < c->track_count; ++i) {
+ imf_virtual_track_playback_context_free(c->tracks[i]);
+ }
+
+ return 0;
+}
+
+static const AVOption imf_options[] = {
+ {"assetmaps", "IMF CPL-related asset map comma-separated absolute paths. If not specified, the CPL sibling `ASSETMAP.xml` file is used.", offsetof(IMFContext, asset_map_paths), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, AV_OPT_FLAG_DECODING_PARAM},
+ {NULL}};
+
+static const AVClass imf_class = {
+ .class_name = "imf",
+ .item_name = av_default_item_name,
+ .option = imf_options,
+ .version = LIBAVUTIL_VERSION_INT,
+};
+
+const AVInputFormat ff_imf_demuxer = {
+ .name = "imf",
+ .long_name = NULL_IF_CONFIG_SMALL("IMF (Interoperable Master Format)"),
+ .priv_class = &imf_class,
+ .priv_data_size = sizeof(IMFContext),
+ .read_header = imf_read_header,
+ .read_packet = ff_imf_read_packet,
+ .read_close = imf_close,
+ .extensions = "xml",
+ .mime_type = "application/xml,text/xml",
+};
--
2.17.1
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