ffmpeg/libavformat/imfdec.c

1011 lines
35 KiB
C

/*
* 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
*/
/*
*
* 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
* @author Nicholas Vanderzwet
* @file
* @ingroup lavu_imf
*/
#include "avio_internal.h"
#include "demux.h"
#include "imf.h"
#include "internal.h"
#include "libavcodec/packet.h"
#include "libavutil/avstring.h"
#include "libavutil/bprint.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/opt.h"
#include "mxf.h"
#include <inttypes.h>
#include <libxml/parser.h>
#define AVRATIONAL_FORMAT "%d/%d"
#define AVRATIONAL_ARG(rational) rational.num, rational.den
/**
* IMF Asset locator
*/
typedef struct IMFAssetLocator {
AVUUID uuid;
char *absolute_uri;
} IMFAssetLocator;
/**
* IMF Asset locator map
* Results from the parsing of one or more ASSETMAP XML files
*/
typedef struct IMFAssetLocatorMap {
uint32_t asset_count;
IMFAssetLocator *assets;
} IMFAssetLocatorMap;
typedef struct IMFVirtualTrackResourcePlaybackCtx {
IMFAssetLocator *locator; /**< Location of the resource */
FFIMFTrackFileResource *resource; /**< Underlying IMF CPL resource */
AVFormatContext *ctx; /**< Context associated with the resource */
AVRational start_time; /**< inclusive start time of the resource on the CPL timeline (s) */
AVRational end_time; /**< exclusive end time of the resource on the CPL timeline (s) */
AVRational ts_offset; /**< start_time minus the entry point into the resource (s) */
} IMFVirtualTrackResourcePlaybackCtx;
typedef struct IMFVirtualTrackPlaybackCtx {
int32_t index; /**< Track index in playlist */
AVRational current_timestamp; /**< Current temporal position */
AVRational duration; /**< Overall duration */
uint32_t resource_count; /**< Number of resources (<= INT32_MAX) */
unsigned int resources_alloc_sz; /**< Size of the buffer holding the resource */
IMFVirtualTrackResourcePlaybackCtx *resources; /**< Buffer holding the resources */
int32_t current_resource_index; /**< Index of the current resource in resources,
or < 0 if a current resource has yet to be selected */
} IMFVirtualTrackPlaybackCtx;
typedef struct IMFContext {
const AVClass *class;
const char *base_url;
char *asset_map_paths;
AVIOInterruptCB *interrupt_callback;
AVDictionary *avio_opts;
FFIMFCPL *cpl;
IMFAssetLocatorMap asset_locator_map;
uint32_t track_count;
IMFVirtualTrackPlaybackCtx **tracks;
} IMFContext;
static int imf_uri_is_url(const char *string)
{
return strstr(string, "://") != NULL;
}
static int imf_uri_is_unix_abs_path(const char *string)
{
return string[0] == '/';
}
static int imf_uri_is_dos_abs_path(const char *string)
{
/* Absolute path case: `C:\path\to\somwhere` */
if (string[1] == ':' && string[2] == '\\')
return 1;
/* Absolute path case: `C:/path/to/somwhere` */
if (string[1] == ':' && string[2] == '/')
return 1;
/* Network path case: `\\path\to\somwhere` */
if (string[0] == '\\' && string[1] == '\\')
return 1;
return 0;
}
static int imf_time_to_ts(int64_t *ts, AVRational t, AVRational time_base)
{
int dst_num;
int dst_den;
AVRational r;
r = av_div_q(t, time_base);
if ((av_reduce(&dst_num, &dst_den, r.num, r.den, INT64_MAX) != 1))
return 1;
if (dst_den != 1)
return 1;
*ts = dst_num;
return 0;
}
/**
* Parse a ASSETMAP XML file to extract the UUID-URI mapping of assets.
* @param s the current format context, if any (can be NULL).
* @param doc the XML document to be parsed.
* @param asset_map pointer on the IMFAssetLocatorMap to fill.
* @param base_url the url of the asset map XML file, if any (can be NULL).
* @return a negative value in case of error, 0 otherwise.
*/
static 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;
xmlNodePtr asset_element = NULL;
unsigned long elem_count;
char *uri;
int ret = 0;
IMFAssetLocator *asset = NULL;
void *tmp;
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 = ff_imf_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;
}
elem_count = xmlChildElementCount(node);
if (elem_count > UINT32_MAX
|| asset_map->asset_count > UINT32_MAX - elem_count)
return AVERROR(ENOMEM);
tmp = av_realloc_array(asset_map->assets,
elem_count + asset_map->asset_count,
sizeof(IMFAssetLocator));
if (!tmp) {
av_log(s, AV_LOG_ERROR, "Cannot allocate IMF asset locators\n");
return AVERROR(ENOMEM);
}
asset_map->assets = tmp;
asset_element = xmlFirstElementChild(node);
while (asset_element) {
if (av_strcasecmp(asset_element->name, "Asset") != 0)
continue;
asset = &(asset_map->assets[asset_map->asset_count]);
if (!(node = ff_imf_xml_get_child_element_by_name(asset_element, "Id"))) {
av_log(s, AV_LOG_ERROR, "Unable to parse asset map XML - missing Id node\n");
return AVERROR_INVALIDDATA;
}
if (ff_imf_xml_read_uuid(node, asset->uuid)) {
av_log(s, AV_LOG_ERROR, "Could not parse UUID from asset in asset map.\n");
return AVERROR_INVALIDDATA;
}
av_log(s, AV_LOG_DEBUG, "Found asset id: " AV_PRI_URN_UUID "\n", AV_UUID_ARG(asset->uuid));
if (!(node = ff_imf_xml_get_child_element_by_name(asset_element, "ChunkList"))) {
av_log(s, AV_LOG_ERROR, "Unable to parse asset map XML - missing ChunkList node\n");
return AVERROR_INVALIDDATA;
}
if (!(node = ff_imf_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(ff_imf_xml_get_child_element_by_name(node, "Path"));
if (!imf_uri_is_url(uri) && !imf_uri_is_unix_abs_path(uri) && !imf_uri_is_dos_abs_path(uri))
asset->absolute_uri = av_append_path_component(base_url, uri);
else
asset->absolute_uri = av_strdup(uri);
xmlFree(uri);
if (!asset->absolute_uri)
return AVERROR(ENOMEM);
av_log(s, AV_LOG_DEBUG, "Found asset absolute URI: %s\n", asset->absolute_uri);
asset_map->asset_count++;
asset_element = xmlNextElementSibling(asset_element);
}
return ret;
}
/**
* Initializes an IMFAssetLocatorMap structure.
*/
static void imf_asset_locator_map_init(IMFAssetLocatorMap *asset_map)
{
asset_map->assets = NULL;
asset_map->asset_count = 0;
}
/**
* Free a IMFAssetLocatorMap pointer.
*/
static void imf_asset_locator_map_deinit(IMFAssetLocatorMap *asset_map)
{
for (uint32_t i = 0; i < asset_map->asset_count; i++)
av_freep(&asset_map->assets[i].absolute_uri);
av_freep(&asset_map->assets);
}
static int parse_assetmap(AVFormatContext *s, const char *url)
{
IMFContext *c = s->priv_data;
AVIOContext *in = NULL;
struct AVBPrint buf;
AVDictionary *opts = NULL;
xmlDoc *doc = NULL;
const char *base_url;
char *tmp_str = NULL;
int ret;
av_log(s, AV_LOG_DEBUG, "Asset Map URL: %s\n", url);
av_dict_copy(&opts, c->avio_opts, 0);
ret = s->io_open(s, &in, url, AVIO_FLAG_READ, &opts);
av_dict_free(&opts);
if (ret < 0)
return ret;
av_bprint_init(&buf, 0, INT_MAX); // xmlReadMemory uses integer length
ret = avio_read_to_bprint(in, &buf, SIZE_MAX);
if (ret < 0 || !avio_feof(in)) {
av_log(s, AV_LOG_ERROR, "Unable to read to asset map '%s'\n", url);
if (ret == 0)
ret = AVERROR_INVALIDDATA;
goto clean_up;
}
LIBXML_TEST_VERSION
tmp_str = av_strdup(url);
if (!tmp_str) {
ret = AVERROR(ENOMEM);
goto clean_up;
}
base_url = av_dirname(tmp_str);
doc = xmlReadMemory(buf.str, buf.len, url, NULL, 0);
ret = parse_imf_asset_map_from_xml_dom(s, doc, &c->asset_locator_map, base_url);
if (!ret)
av_log(s, AV_LOG_DEBUG, "Found %d assets from %s\n",
c->asset_locator_map.asset_count, url);
xmlFreeDoc(doc);
clean_up:
if (tmp_str)
av_freep(&tmp_str);
ff_format_io_close(s, &in);
av_bprint_finalize(&buf, NULL);
return ret;
}
static IMFAssetLocator *find_asset_map_locator(IMFAssetLocatorMap *asset_map, AVUUID uuid)
{
for (uint32_t i = 0; i < asset_map->asset_count; i++) {
if (memcmp(asset_map->assets[i].uuid, uuid, 16) == 0)
return &(asset_map->assets[i]);
}
return NULL;
}
static int open_track_resource_context(AVFormatContext *s,
IMFVirtualTrackPlaybackCtx *track,
int32_t resource_index)
{
IMFContext *c = s->priv_data;
int ret = 0;
int64_t seek_offset = 0;
AVDictionary *opts = NULL;
AVStream *st;
IMFVirtualTrackResourcePlaybackCtx *track_resource = track->resources + resource_index;
if (track_resource->ctx) {
av_log(s, AV_LOG_DEBUG, "Input context already opened for %s.\n",
track_resource->locator->absolute_uri);
return 0;
}
track_resource->ctx = avformat_alloc_context();
if (!track_resource->ctx)
return AVERROR(ENOMEM);
track_resource->ctx->io_open = s->io_open;
track_resource->ctx->io_close = s->io_close;
track_resource->ctx->io_close2 = s->io_close2;
track_resource->ctx->flags |= s->flags & ~AVFMT_FLAG_CUSTOM_IO;
if ((ret = ff_copy_whiteblacklists(track_resource->ctx, s)) < 0)
goto cleanup;
if ((ret = av_opt_set(track_resource->ctx, "format_whitelist", "mxf", 0)))
goto cleanup;
if ((ret = av_dict_copy(&opts, c->avio_opts, 0)) < 0)
goto cleanup;
ret = avformat_open_input(&track_resource->ctx,
track_resource->locator->absolute_uri,
NULL,
&opts);
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;
}
av_dict_free(&opts);
/* make sure there is only one stream in the file */
if (track_resource->ctx->nb_streams != 1) {
ret = AVERROR_INVALIDDATA;
goto cleanup;
}
st = track_resource->ctx->streams[0];
/* Determine the seek offset into the Track File, taking into account:
* - the current timestamp within the virtual track
* - the entry point of the resource
*/
if (imf_time_to_ts(&seek_offset,
av_sub_q(track->current_timestamp, track_resource->ts_offset),
st->time_base))
av_log(s, AV_LOG_WARNING, "Incoherent stream timebase " AVRATIONAL_FORMAT
"and composition timeline position: " AVRATIONAL_FORMAT "\n",
AVRATIONAL_ARG(st->time_base), AVRATIONAL_ARG(track->current_timestamp));
if (seek_offset) {
av_log(s, AV_LOG_DEBUG, "Seek at resource %s entry point: %" PRIi64 "\n",
track_resource->locator->absolute_uri, seek_offset);
ret = avformat_seek_file(track_resource->ctx, 0, seek_offset, seek_offset, seek_offset, 0);
if (ret < 0) {
av_log(s,
AV_LOG_ERROR,
"Could not seek at %" PRId64 "on %s: %s\n",
seek_offset,
track_resource->locator->absolute_uri,
av_err2str(ret));
avformat_close_input(&track_resource->ctx);
return ret;
}
}
return 0;
cleanup:
av_dict_free(&opts);
avformat_free_context(track_resource->ctx);
track_resource->ctx = NULL;
return ret;
}
static int open_track_file_resource(AVFormatContext *s,
FFIMFTrackFileResource *track_file_resource,
IMFVirtualTrackPlaybackCtx *track)
{
IMFContext *c = s->priv_data;
IMFAssetLocator *asset_locator;
void *tmp;
asset_locator = find_asset_map_locator(&c->asset_locator_map, track_file_resource->track_file_uuid);
if (!asset_locator) {
av_log(s, AV_LOG_ERROR, "Could not find asset locator for UUID: " AV_PRI_URN_UUID "\n",
AV_UUID_ARG(track_file_resource->track_file_uuid));
return AVERROR_INVALIDDATA;
}
av_log(s,
AV_LOG_DEBUG,
"Found locator for " AV_PRI_URN_UUID ": %s\n",
AV_UUID_ARG(asset_locator->uuid),
asset_locator->absolute_uri);
if (track->resource_count > INT32_MAX - track_file_resource->base.repeat_count
|| (track->resource_count + track_file_resource->base.repeat_count)
> INT_MAX / sizeof(IMFVirtualTrackResourcePlaybackCtx))
return AVERROR(ENOMEM);
tmp = av_fast_realloc(track->resources,
&track->resources_alloc_sz,
(track->resource_count + track_file_resource->base.repeat_count)
* sizeof(IMFVirtualTrackResourcePlaybackCtx));
if (!tmp)
return AVERROR(ENOMEM);
track->resources = tmp;
for (uint32_t i = 0; i < track_file_resource->base.repeat_count; i++) {
IMFVirtualTrackResourcePlaybackCtx vt_ctx;
vt_ctx.locator = asset_locator;
vt_ctx.resource = track_file_resource;
vt_ctx.ctx = NULL;
vt_ctx.start_time = track->duration;
vt_ctx.ts_offset = av_sub_q(vt_ctx.start_time,
av_div_q(av_make_q((int)track_file_resource->base.entry_point, 1),
track_file_resource->base.edit_rate));
vt_ctx.end_time = av_add_q(track->duration,
av_make_q((int)track_file_resource->base.duration
* track_file_resource->base.edit_rate.den,
track_file_resource->base.edit_rate.num));
track->resources[track->resource_count++] = vt_ctx;
track->duration = vt_ctx.end_time;
}
return 0;
}
static void imf_virtual_track_playback_context_deinit(IMFVirtualTrackPlaybackCtx *track)
{
for (uint32_t i = 0; i < track->resource_count; i++)
avformat_close_input(&track->resources[i].ctx);
av_freep(&track->resources);
}
static int open_virtual_track(AVFormatContext *s,
FFIMFTrackFileVirtualTrack *virtual_track,
int32_t track_index)
{
IMFContext *c = s->priv_data;
IMFVirtualTrackPlaybackCtx *track = NULL;
void *tmp;
int ret = 0;
if (!(track = av_mallocz(sizeof(IMFVirtualTrackPlaybackCtx))))
return AVERROR(ENOMEM);
track->current_resource_index = -1;
track->index = track_index;
track->duration = av_make_q(0, 1);
for (uint32_t i = 0; i < virtual_track->resource_count; i++) {
av_log(s,
AV_LOG_DEBUG,
"Open stream from file " AV_PRI_URN_UUID ", stream %d\n",
AV_UUID_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 " AV_PRI_URN_UUID "\n",
AV_UUID_ARG(virtual_track->resources[i].track_file_uuid));
goto clean_up;
}
}
track->current_timestamp = av_make_q(0, track->duration.den);
if (c->track_count == UINT32_MAX) {
ret = AVERROR(ENOMEM);
goto clean_up;
}
tmp = av_realloc_array(c->tracks, c->track_count + 1, sizeof(IMFVirtualTrackPlaybackCtx *));
if (!tmp) {
ret = AVERROR(ENOMEM);
goto clean_up;
}
c->tracks = tmp;
c->tracks[c->track_count++] = track;
return 0;
clean_up:
imf_virtual_track_playback_context_deinit(track);
av_free(track);
return ret;
}
static int set_context_streams_from_tracks(AVFormatContext *s)
{
IMFContext *c = s->priv_data;
int ret = 0;
for (uint32_t i = 0; i < c->track_count; i++) {
AVStream *asset_stream;
AVStream *first_resource_stream;
/* Open the first resource of the track to get stream information */
ret = open_track_resource_context(s, c->tracks[i], 0);
if (ret)
return ret;
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);
asset_stream = ff_stream_clone(s, first_resource_stream);
if (!asset_stream) {
av_log(s, AV_LOG_ERROR, "Could not clone stream\n");
return AVERROR(ENOMEM);
}
asset_stream->id = i;
asset_stream->nb_frames = 0;
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 0;
}
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 " AV_PRI_URN_UUID "\n",
AV_UUID_ARG(c->cpl->main_image_2d_track->base.id_uuid));
return ret;
}
}
for (uint32_t i = 0; i < c->cpl->main_audio_track_count; i++) {
if ((ret = open_virtual_track(s, &c->cpl->main_audio_tracks[i], track_index++)) != 0) {
av_log(s, AV_LOG_ERROR, "Could not open audio track " AV_PRI_URN_UUID "\n",
AV_UUID_ARG(c->cpl->main_audio_tracks[i].base.id_uuid));
return ret;
}
}
return set_context_streams_from_tracks(s);
}
static int imf_read_header(AVFormatContext *s)
{
IMFContext *c = s->priv_data;
char *asset_map_path;
char *tmp_str;
int ret = 0;
c->interrupt_callback = &s->interrupt_callback;
tmp_str = av_strdup(s->url);
if (!tmp_str)
return AVERROR(ENOMEM);
c->base_url = av_strdup(av_dirname(tmp_str));
av_freep(&tmp_str);
if (!c->base_url)
return AVERROR(ENOMEM);
if ((ret = ffio_copy_url_options(s->pb, &c->avio_opts)) < 0)
return ret;
av_log(s, AV_LOG_DEBUG, "start parsing IMF CPL: %s\n", s->url);
if ((ret = ff_imf_parse_cpl(s->pb, &c->cpl)) < 0)
return ret;
av_log(s,
AV_LOG_DEBUG,
"parsed IMF CPL: " AV_PRI_URN_UUID "\n",
AV_UUID_ARG(c->cpl->id_uuid));
if (!c->asset_map_paths) {
c->asset_map_paths = av_append_path_component(c->base_url, "ASSETMAP.xml");
if (!c->asset_map_paths) {
ret = AVERROR(ENOMEM);
return ret;
}
av_log(s, AV_LOG_DEBUG, "No asset maps provided, using the default ASSETMAP.xml\n");
}
/* Parse each asset map XML file */
imf_asset_locator_map_init(&c->asset_locator_map);
asset_map_path = av_strtok(c->asset_map_paths, ",", &tmp_str);
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)))
return ret;
asset_map_path = av_strtok(NULL, ",", &tmp_str);
}
av_log(s, AV_LOG_DEBUG, "parsed IMF Asset Maps\n");
if ((ret = open_cpl_tracks(s)))
return ret;
av_log(s, AV_LOG_DEBUG, "parsed IMF package\n");
return 0;
}
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 (uint32_t i = c->track_count; i > 0; i--) {
av_log(s, AV_LOG_TRACE, "Compare track %d timestamp " AVRATIONAL_FORMAT
" to minimum " AVRATIONAL_FORMAT
" (over duration: " AVRATIONAL_FORMAT ")\n", i,
AVRATIONAL_ARG(c->tracks[i - 1]->current_timestamp),
AVRATIONAL_ARG(minimum_timestamp),
AVRATIONAL_ARG(c->tracks[i - 1]->duration));
if (av_cmp_q(c->tracks[i - 1]->current_timestamp, minimum_timestamp) <= 0) {
track = c->tracks[i - 1];
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 int get_resource_context_for_timestamp(AVFormatContext *s, IMFVirtualTrackPlaybackCtx *track, IMFVirtualTrackResourcePlaybackCtx **resource)
{
*resource = NULL;
if (av_cmp_q(track->current_timestamp, track->duration) >= 0) {
av_log(s, AV_LOG_DEBUG, "Reached the end of the virtual track\n");
return AVERROR_EOF;
}
av_log(s,
AV_LOG_TRACE,
"Looking for track %d resource for timestamp = %lf / %lf\n",
track->index,
av_q2d(track->current_timestamp),
av_q2d(track->duration));
for (uint32_t i = 0; i < track->resource_count; i++) {
if (av_cmp_q(track->resources[i].end_time, track->current_timestamp) > 0) {
av_log(s, AV_LOG_DEBUG, "Found resource %d in track %d to read at timestamp %lf: "
"entry=%" PRIu32 ", duration=%" PRIu32 ", editrate=" AVRATIONAL_FORMAT "\n",
i, track->index, av_q2d(track->current_timestamp),
track->resources[i].resource->base.entry_point,
track->resources[i].resource->base.duration,
AVRATIONAL_ARG(track->resources[i].resource->base.edit_rate));
if (track->current_resource_index != i) {
int ret;
av_log(s, AV_LOG_TRACE, "Switch resource on track %d: re-open context\n",
track->index);
ret = open_track_resource_context(s, track, i);
if (ret != 0)
return ret;
if (track->current_resource_index > 0)
avformat_close_input(&track->resources[track->current_resource_index].ctx);
track->current_resource_index = i;
}
*resource = track->resources + track->current_resource_index;
return 0;
}
}
av_log(s, AV_LOG_ERROR, "Could not find IMF track resource to read\n");
return AVERROR_STREAM_NOT_FOUND;
}
static int imf_read_packet(AVFormatContext *s, AVPacket *pkt)
{
IMFVirtualTrackResourcePlaybackCtx *resource = NULL;
int ret = 0;
IMFVirtualTrackPlaybackCtx *track;
int64_t delta_ts;
AVStream *st;
AVRational next_timestamp;
track = get_next_track_with_minimum_timestamp(s);
ret = get_resource_context_for_timestamp(s, track, &resource);
if (ret)
return ret;
ret = av_read_frame(resource->ctx, pkt);
if (ret)
return ret;
av_log(s, AV_LOG_DEBUG, "Got packet: pts=%" PRId64 ", dts=%" PRId64
", duration=%" PRId64 ", stream_index=%d, pos=%" PRId64
", time_base=" AVRATIONAL_FORMAT "\n", pkt->pts, pkt->dts, pkt->duration,
pkt->stream_index, pkt->pos, AVRATIONAL_ARG(pkt->time_base));
/* IMF resources contain only one stream */
if (pkt->stream_index != 0)
return AVERROR_INVALIDDATA;
st = resource->ctx->streams[0];
pkt->stream_index = track->index;
/* adjust the packet PTS and DTS based on the temporal position of the resource within the timeline */
ret = imf_time_to_ts(&delta_ts, resource->ts_offset, st->time_base);
if (!ret) {
if (pkt->pts != AV_NOPTS_VALUE)
pkt->pts += delta_ts;
if (pkt->dts != AV_NOPTS_VALUE)
pkt->dts += delta_ts;
} else {
av_log(s, AV_LOG_WARNING, "Incoherent time stamp " AVRATIONAL_FORMAT
" for time base " AVRATIONAL_FORMAT,
AVRATIONAL_ARG(resource->ts_offset),
AVRATIONAL_ARG(pkt->time_base));
}
/* advance the track timestamp by the packet duration */
next_timestamp = av_add_q(track->current_timestamp,
av_mul_q(av_make_q((int)pkt->duration, 1), st->time_base));
/* if necessary, clamp the next timestamp to the end of the current resource */
if (av_cmp_q(next_timestamp, resource->end_time) > 0) {
int64_t new_pkt_dur;
/* shrink the packet duration */
ret = imf_time_to_ts(&new_pkt_dur,
av_sub_q(resource->end_time, track->current_timestamp),
st->time_base);
if (!ret)
pkt->duration = new_pkt_dur;
else
av_log(s, AV_LOG_WARNING, "Incoherent time base in packet duration calculation\n");
/* shrink the packet itself for audio essence */
if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
if (st->codecpar->codec_id == AV_CODEC_ID_PCM_S24LE) {
/* AV_CODEC_ID_PCM_S24LE is the only PCM format supported in IMF */
/* in this case, explicitly shrink the packet */
int bytes_per_sample = av_get_exact_bits_per_sample(st->codecpar->codec_id) >> 3;
int64_t nbsamples = av_rescale_q(pkt->duration,
st->time_base,
av_make_q(1, st->codecpar->sample_rate));
av_shrink_packet(pkt, nbsamples * st->codecpar->ch_layout.nb_channels * bytes_per_sample);
} else {
/* in all other cases, use side data to skip samples */
int64_t skip_samples;
ret = imf_time_to_ts(&skip_samples,
av_sub_q(next_timestamp, resource->end_time),
av_make_q(1, st->codecpar->sample_rate));
if (ret || skip_samples < 0 || skip_samples > UINT32_MAX) {
av_log(s, AV_LOG_WARNING, "Cannot skip audio samples\n");
} else {
uint8_t *side_data = av_packet_new_side_data(pkt, AV_PKT_DATA_SKIP_SAMPLES, 10);
if (!side_data)
return AVERROR(ENOMEM);
AV_WL32(side_data + 4, skip_samples); /* skip from end of this packet */
side_data[6] = 1; /* reason for end is convergence */
}
}
next_timestamp = resource->end_time;
} else {
av_log(s, AV_LOG_WARNING, "Non-audio packet duration reduced\n");
}
}
track->current_timestamp = next_timestamp;
return 0;
}
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_deinit(&c->asset_locator_map);
ff_imf_cpl_free(c->cpl);
for (uint32_t i = 0; i < c->track_count; i++) {
imf_virtual_track_playback_context_deinit(c->tracks[i]);
av_freep(&c->tracks[i]);
}
av_freep(&c->tracks);
return 0;
}
static int imf_probe(const AVProbeData *p)
{
if (!strstr(p->buf, "<CompositionPlaylist"))
return 0;
/* check for a ContentTitle element without including ContentTitleText,
* which is used by the D-Cinema CPL.
*/
if (!strstr(p->buf, "ContentTitle>"))
return 0;
return AVPROBE_SCORE_MAX;
}
static int coherent_ts(int64_t ts, AVRational in_tb, AVRational out_tb)
{
int dst_num;
int dst_den;
int ret;
ret = av_reduce(&dst_num, &dst_den, ts * in_tb.num * out_tb.den,
in_tb.den * out_tb.num, INT64_MAX);
if (!ret || dst_den != 1)
return 0;
return 1;
}
static int imf_seek(AVFormatContext *s, int stream_index, int64_t min_ts,
int64_t ts, int64_t max_ts, int flags)
{
IMFContext *c = s->priv_data;
uint32_t i;
if (flags & (AVSEEK_FLAG_BYTE | AVSEEK_FLAG_FRAME))
return AVERROR(ENOSYS);
/* rescale timestamps to Composition edit units */
if (stream_index < 0)
ff_rescale_interval(AV_TIME_BASE_Q,
av_make_q(c->cpl->edit_rate.den, c->cpl->edit_rate.num),
&min_ts, &ts, &max_ts);
else
ff_rescale_interval(s->streams[stream_index]->time_base,
av_make_q(c->cpl->edit_rate.den, c->cpl->edit_rate.num),
&min_ts, &ts, &max_ts);
/* requested timestamp bounds are too close */
if (max_ts < min_ts)
return -1;
/* clamp requested timestamp to provided bounds */
ts = FFMAX(FFMIN(ts, max_ts), min_ts);
av_log(s, AV_LOG_DEBUG, "Seeking to Composition Playlist edit unit %" PRIi64 "\n", ts);
/* set the dts of each stream and temporal offset of each track */
for (i = 0; i < c->track_count; i++) {
AVStream *st = s->streams[i];
IMFVirtualTrackPlaybackCtx *t = c->tracks[i];
int64_t dts;
if (!coherent_ts(ts, av_make_q(c->cpl->edit_rate.den, c->cpl->edit_rate.num),
st->time_base))
av_log(s, AV_LOG_WARNING, "Seek position is not coherent across tracks\n");
dts = av_rescale(ts,
st->time_base.den * c->cpl->edit_rate.den,
st->time_base.num * c->cpl->edit_rate.num);
av_log(s, AV_LOG_DEBUG, "Seeking to dts=%" PRId64 " on stream_index=%d\n",
dts, i);
t->current_timestamp = av_mul_q(av_make_q(dts, 1), st->time_base);
if (t->current_resource_index >= 0) {
avformat_close_input(&t->resources[t->current_resource_index].ctx);
t->current_resource_index = -1;
}
}
return 0;
}
static const AVOption imf_options[] = {
{
.name = "assetmaps",
.help = "Comma-separated paths to ASSETMAP files."
"If not specified, the `ASSETMAP.xml` file in the same "
"directory as the CPL is used.",
.offset = offsetof(IMFContext, asset_map_paths),
.type = AV_OPT_TYPE_STRING,
.default_val = {.str = NULL},
.flags = 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)"),
.flags = AVFMT_EXPERIMENTAL | AVFMT_NO_BYTE_SEEK,
.flags_internal = FF_FMT_INIT_CLEANUP,
.priv_class = &imf_class,
.priv_data_size = sizeof(IMFContext),
.read_probe = imf_probe,
.read_header = imf_read_header,
.read_packet = imf_read_packet,
.read_close = imf_close,
.read_seek2 = imf_seek,
};