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FFmpeg/libavcodec/mmaldec.c

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/*
* MMAL Video Decoder
* Copyright (c) 2015 Rodger Combs
*
* 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
*/
/**
* @file
* MMAL Video Decoder
*/
#include <bcm_host.h>
#include <interface/mmal/mmal.h>
#include <interface/mmal/mmal_parameters_video.h>
#include <interface/mmal/util/mmal_util.h>
#include <interface/mmal/util/mmal_util_params.h>
#include <interface/mmal/util/mmal_default_components.h>
#include <interface/mmal/vc/mmal_vc_api.h>
#include <stdatomic.h>
#include "avcodec.h"
#include "internal.h"
#include "libavutil/avassert.h"
#include "libavutil/buffer.h"
#include "libavutil/common.h"
#include "libavutil/imgutils.h"
#include "libavutil/opt.h"
#include "libavutil/log.h"
typedef struct FFBufferEntry {
AVBufferRef *ref;
void *data;
size_t length;
int64_t pts, dts;
int flags;
struct FFBufferEntry *next;
} FFBufferEntry;
// MMAL_POOL_T destroys all of its MMAL_BUFFER_HEADER_Ts. If we want correct
// refcounting for AVFrames, we can free the MMAL_POOL_T only after all AVFrames
// have been unreferenced.
typedef struct FFPoolRef {
atomic_int refcount;
MMAL_POOL_T *pool;
} FFPoolRef;
typedef struct FFBufferRef {
MMAL_BUFFER_HEADER_T *buffer;
FFPoolRef *pool;
} FFBufferRef;
typedef struct MMALDecodeContext {
AVClass *av_class;
int extra_buffers;
int extra_decoder_buffers;
MMAL_COMPONENT_T *decoder;
MMAL_QUEUE_T *queue_decoded_frames;
MMAL_POOL_T *pool_in;
FFPoolRef *pool_out;
// Waiting input packets. Because the libavcodec API requires decoding and
// returning packets in lockstep, it can happen that queue_decoded_frames
// contains almost all surfaces - then the decoder input queue can quickly
// fill up and won't accept new input either. Without consuming input, the
// libavcodec API can't return new frames, and we have a logical deadlock.
// This is avoided by queuing such buffers here.
FFBufferEntry *waiting_buffers, *waiting_buffers_tail;
int64_t packets_sent;
atomic_int packets_buffered;
int64_t frames_output;
int eos_received;
int eos_sent;
int extradata_sent;
int interlaced_frame;
int top_field_first;
} MMALDecodeContext;
// Assume decoder is guaranteed to produce output after at least this many
// packets (where each packet contains 1 frame).
#define MAX_DELAYED_FRAMES 16
static void ffmmal_poolref_unref(FFPoolRef *ref)
{
if (ref &&
atomic_fetch_add_explicit(&ref->refcount, -1, memory_order_acq_rel) == 1) {
mmal_pool_destroy(ref->pool);
av_free(ref);
}
}
static void ffmmal_release_frame(void *opaque, uint8_t *data)
{
FFBufferRef *ref = (void *)data;
mmal_buffer_header_release(ref->buffer);
ffmmal_poolref_unref(ref->pool);
av_free(ref);
}
// Setup frame with a new reference to buffer. The buffer must have been
// allocated from the given pool.
static int ffmmal_set_ref(AVFrame *frame, FFPoolRef *pool,
MMAL_BUFFER_HEADER_T *buffer)
{
FFBufferRef *ref = av_mallocz(sizeof(*ref));
if (!ref)
return AVERROR(ENOMEM);
ref->pool = pool;
ref->buffer = buffer;
frame->buf[0] = av_buffer_create((void *)ref, sizeof(*ref),
ffmmal_release_frame, NULL,
AV_BUFFER_FLAG_READONLY);
if (!frame->buf[0]) {
av_free(ref);
return AVERROR(ENOMEM);
}
atomic_fetch_add_explicit(&ref->pool->refcount, 1, memory_order_relaxed);
mmal_buffer_header_acquire(buffer);
frame->format = AV_PIX_FMT_MMAL;
frame->data[3] = (uint8_t *)ref->buffer;
return 0;
}
static void ffmmal_stop_decoder(AVCodecContext *avctx)
{
MMALDecodeContext *ctx = avctx->priv_data;
MMAL_COMPONENT_T *decoder = ctx->decoder;
MMAL_BUFFER_HEADER_T *buffer;
mmal_port_disable(decoder->input[0]);
mmal_port_disable(decoder->output[0]);
mmal_port_disable(decoder->control);
mmal_port_flush(decoder->input[0]);
mmal_port_flush(decoder->output[0]);
mmal_port_flush(decoder->control);
while ((buffer = mmal_queue_get(ctx->queue_decoded_frames)))
mmal_buffer_header_release(buffer);
while (ctx->waiting_buffers) {
FFBufferEntry *buffer = ctx->waiting_buffers;
ctx->waiting_buffers = buffer->next;
if (buffer->flags & MMAL_BUFFER_HEADER_FLAG_FRAME_END)
atomic_fetch_add(&ctx->packets_buffered, -1);
av_buffer_unref(&buffer->ref);
av_free(buffer);
}
ctx->waiting_buffers_tail = NULL;
av_assert0(atomic_load(&ctx->packets_buffered) == 0);
ctx->frames_output = ctx->eos_received = ctx->eos_sent = ctx->packets_sent = ctx->extradata_sent = 0;
}
static av_cold int ffmmal_close_decoder(AVCodecContext *avctx)
{
MMALDecodeContext *ctx = avctx->priv_data;
if (ctx->decoder)
ffmmal_stop_decoder(avctx);
mmal_component_destroy(ctx->decoder);
ctx->decoder = NULL;
mmal_queue_destroy(ctx->queue_decoded_frames);
mmal_pool_destroy(ctx->pool_in);
ffmmal_poolref_unref(ctx->pool_out);
mmal_vc_deinit();
return 0;
}
static void input_callback(MMAL_PORT_T *port, MMAL_BUFFER_HEADER_T *buffer)
{
AVCodecContext *avctx = (AVCodecContext*)port->userdata;
MMALDecodeContext *ctx = avctx->priv_data;
if (!buffer->cmd) {
FFBufferEntry *entry = buffer->user_data;
av_buffer_unref(&entry->ref);
if (entry->flags & MMAL_BUFFER_HEADER_FLAG_FRAME_END)
atomic_fetch_add(&ctx->packets_buffered, -1);
av_free(entry);
}
mmal_buffer_header_release(buffer);
}
static void output_callback(MMAL_PORT_T *port, MMAL_BUFFER_HEADER_T *buffer)
{
AVCodecContext *avctx = (AVCodecContext*)port->userdata;
MMALDecodeContext *ctx = avctx->priv_data;
mmal_queue_put(ctx->queue_decoded_frames, buffer);
}
static void control_port_cb(MMAL_PORT_T *port, MMAL_BUFFER_HEADER_T *buffer)
{
AVCodecContext *avctx = (AVCodecContext*)port->userdata;
MMAL_STATUS_T status;
if (buffer->cmd == MMAL_EVENT_ERROR) {
status = *(uint32_t *)buffer->data;
av_log(avctx, AV_LOG_ERROR, "MMAL error %d on control port\n", (int)status);
} else {
char s[20];
av_get_codec_tag_string(s, sizeof(s), buffer->cmd);
av_log(avctx, AV_LOG_WARNING, "Unknown MMAL event %s on control port\n", s);
}
mmal_buffer_header_release(buffer);
}
// Feed free output buffers to the decoder.
static int ffmmal_fill_output_port(AVCodecContext *avctx)
{
MMALDecodeContext *ctx = avctx->priv_data;
MMAL_BUFFER_HEADER_T *buffer;
MMAL_STATUS_T status;
if (!ctx->pool_out)
return AVERROR_UNKNOWN; // format change code failed with OOM previously
while ((buffer = mmal_queue_get(ctx->pool_out->pool->queue))) {
if ((status = mmal_port_send_buffer(ctx->decoder->output[0], buffer))) {
mmal_buffer_header_release(buffer);
av_log(avctx, AV_LOG_ERROR, "MMAL error %d when sending output buffer.\n", (int)status);
return AVERROR_UNKNOWN;
}
}
return 0;
}
static enum AVColorSpace ffmmal_csp_to_av_csp(MMAL_FOURCC_T fourcc)
{
switch (fourcc) {
case MMAL_COLOR_SPACE_BT470_2_BG:
case MMAL_COLOR_SPACE_BT470_2_M:
case MMAL_COLOR_SPACE_ITUR_BT601: return AVCOL_SPC_BT470BG;
case MMAL_COLOR_SPACE_ITUR_BT709: return AVCOL_SPC_BT709;
case MMAL_COLOR_SPACE_FCC: return AVCOL_SPC_FCC;
case MMAL_COLOR_SPACE_SMPTE240M: return AVCOL_SPC_SMPTE240M;
default: return AVCOL_SPC_UNSPECIFIED;
}
}
static int ffmal_update_format(AVCodecContext *avctx)
{
MMALDecodeContext *ctx = avctx->priv_data;
MMAL_STATUS_T status;
int ret = 0;
MMAL_COMPONENT_T *decoder = ctx->decoder;
MMAL_ES_FORMAT_T *format_out = decoder->output[0]->format;
MMAL_PARAMETER_VIDEO_INTERLACE_TYPE_T interlace_type;
ffmmal_poolref_unref(ctx->pool_out);
if (!(ctx->pool_out = av_mallocz(sizeof(*ctx->pool_out)))) {
ret = AVERROR(ENOMEM);
goto fail;
}
atomic_store(&ctx->pool_out->refcount, 1);
if (!format_out)
goto fail;
if ((status = mmal_port_parameter_set_uint32(decoder->output[0], MMAL_PARAMETER_EXTRA_BUFFERS, ctx->extra_buffers)))
goto fail;
if ((status = mmal_port_parameter_set_boolean(decoder->output[0], MMAL_PARAMETER_VIDEO_INTERPOLATE_TIMESTAMPS, 0)))
goto fail;
if (avctx->pix_fmt == AV_PIX_FMT_MMAL) {
format_out->encoding = MMAL_ENCODING_OPAQUE;
} else {
format_out->encoding_variant = format_out->encoding = MMAL_ENCODING_I420;
}
if ((status = mmal_port_format_commit(decoder->output[0])))
goto fail;
interlace_type.hdr.id = MMAL_PARAMETER_VIDEO_INTERLACE_TYPE;
interlace_type.hdr.size = sizeof(MMAL_PARAMETER_VIDEO_INTERLACE_TYPE_T);
status = mmal_port_parameter_get(decoder->output[0], &interlace_type.hdr);
if (status != MMAL_SUCCESS) {
av_log(avctx, AV_LOG_ERROR, "Cannot read MMAL interlace information!\n");
} else {
ctx->interlaced_frame = (interlace_type.eMode != MMAL_InterlaceProgressive);
ctx->top_field_first = (interlace_type.eMode == MMAL_InterlaceFieldsInterleavedUpperFirst);
}
if ((ret = ff_set_dimensions(avctx, format_out->es->video.crop.x + format_out->es->video.crop.width,
format_out->es->video.crop.y + format_out->es->video.crop.height)) < 0)
goto fail;
if (format_out->es->video.par.num && format_out->es->video.par.den) {
avctx->sample_aspect_ratio.num = format_out->es->video.par.num;
avctx->sample_aspect_ratio.den = format_out->es->video.par.den;
}
if (format_out->es->video.frame_rate.num && format_out->es->video.frame_rate.den) {
avctx->framerate.num = format_out->es->video.frame_rate.num;
avctx->framerate.den = format_out->es->video.frame_rate.den;
}
avctx->colorspace = ffmmal_csp_to_av_csp(format_out->es->video.color_space);
decoder->output[0]->buffer_size =
FFMAX(decoder->output[0]->buffer_size_min, decoder->output[0]->buffer_size_recommended);
decoder->output[0]->buffer_num =
FFMAX(decoder->output[0]->buffer_num_min, decoder->output[0]->buffer_num_recommended) + ctx->extra_buffers;
ctx->pool_out->pool = mmal_pool_create(decoder->output[0]->buffer_num,
decoder->output[0]->buffer_size);
if (!ctx->pool_out->pool) {
ret = AVERROR(ENOMEM);
goto fail;
}
return 0;
fail:
return ret < 0 ? ret : AVERROR_UNKNOWN;
}
static av_cold int ffmmal_init_decoder(AVCodecContext *avctx)
{
MMALDecodeContext *ctx = avctx->priv_data;
MMAL_STATUS_T status;
MMAL_ES_FORMAT_T *format_in;
MMAL_COMPONENT_T *decoder;
char tmp[32];
int ret = 0;
bcm_host_init();
if (mmal_vc_init()) {
av_log(avctx, AV_LOG_ERROR, "Cannot initialize MMAL VC driver!\n");
return AVERROR(ENOSYS);
}
if ((ret = ff_get_format(avctx, avctx->codec->pix_fmts)) < 0)
return ret;
avctx->pix_fmt = ret;
if ((status = mmal_component_create(MMAL_COMPONENT_DEFAULT_VIDEO_DECODER, &ctx->decoder)))
goto fail;
decoder = ctx->decoder;
format_in = decoder->input[0]->format;
format_in->type = MMAL_ES_TYPE_VIDEO;
switch (avctx->codec_id) {
case AV_CODEC_ID_MPEG2VIDEO:
format_in->encoding = MMAL_ENCODING_MP2V;
break;
case AV_CODEC_ID_MPEG4:
format_in->encoding = MMAL_ENCODING_MP4V;
break;
case AV_CODEC_ID_VC1:
format_in->encoding = MMAL_ENCODING_WVC1;
break;
case AV_CODEC_ID_H264:
default:
format_in->encoding = MMAL_ENCODING_H264;
break;
}
format_in->es->video.width = FFALIGN(avctx->width, 32);
format_in->es->video.height = FFALIGN(avctx->height, 16);
format_in->es->video.crop.width = avctx->width;
format_in->es->video.crop.height = avctx->height;
format_in->es->video.frame_rate.num = 24000;
format_in->es->video.frame_rate.den = 1001;
format_in->es->video.par.num = avctx->sample_aspect_ratio.num;
format_in->es->video.par.den = avctx->sample_aspect_ratio.den;
format_in->flags = MMAL_ES_FORMAT_FLAG_FRAMED;
av_get_codec_tag_string(tmp, sizeof(tmp), format_in->encoding);
av_log(avctx, AV_LOG_DEBUG, "Using MMAL %s encoding.\n", tmp);
#if HAVE_MMAL_PARAMETER_VIDEO_MAX_NUM_CALLBACKS
if (mmal_port_parameter_set_uint32(decoder->input[0], MMAL_PARAMETER_VIDEO_MAX_NUM_CALLBACKS,
-1 - ctx->extra_decoder_buffers)) {
av_log(avctx, AV_LOG_WARNING, "Could not set input buffering limit.\n");
}
#endif
if ((status = mmal_port_format_commit(decoder->input[0])))
goto fail;
decoder->input[0]->buffer_num =
FFMAX(decoder->input[0]->buffer_num_min, 20);
decoder->input[0]->buffer_size =
FFMAX(decoder->input[0]->buffer_size_min, 512 * 1024);
ctx->pool_in = mmal_pool_create(decoder->input[0]->buffer_num, 0);
if (!ctx->pool_in) {
ret = AVERROR(ENOMEM);
goto fail;
}
if ((ret = ffmal_update_format(avctx)) < 0)
goto fail;
ctx->queue_decoded_frames = mmal_queue_create();
if (!ctx->queue_decoded_frames)
goto fail;
decoder->input[0]->userdata = (void*)avctx;
decoder->output[0]->userdata = (void*)avctx;
decoder->control->userdata = (void*)avctx;
if ((status = mmal_port_enable(decoder->control, control_port_cb)))
goto fail;
if ((status = mmal_port_enable(decoder->input[0], input_callback)))
goto fail;
if ((status = mmal_port_enable(decoder->output[0], output_callback)))
goto fail;
if ((status = mmal_component_enable(decoder)))
goto fail;
return 0;
fail:
ffmmal_close_decoder(avctx);
return ret < 0 ? ret : AVERROR_UNKNOWN;
}
static void ffmmal_flush(AVCodecContext *avctx)
{
MMALDecodeContext *ctx = avctx->priv_data;
MMAL_COMPONENT_T *decoder = ctx->decoder;
MMAL_STATUS_T status;
ffmmal_stop_decoder(avctx);
if ((status = mmal_port_enable(decoder->control, control_port_cb)))
goto fail;
if ((status = mmal_port_enable(decoder->input[0], input_callback)))
goto fail;
if ((status = mmal_port_enable(decoder->output[0], output_callback)))
goto fail;
return;
fail:
av_log(avctx, AV_LOG_ERROR, "MMAL flush error: %i\n", (int)status);
}
// Split packets and add them to the waiting_buffers list. We don't queue them
// immediately, because it can happen that the decoder is temporarily blocked
// (due to us not reading/returning enough output buffers) and won't accept
// new input. (This wouldn't be an issue if MMAL input buffers always were
// complete frames - then the input buffer just would have to be big enough.)
// If is_extradata is set, send it as MMAL_BUFFER_HEADER_FLAG_CONFIG.
static int ffmmal_add_packet(AVCodecContext *avctx, AVPacket *avpkt,
int is_extradata)
{
MMALDecodeContext *ctx = avctx->priv_data;
AVBufferRef *buf = NULL;
int size = 0;
uint8_t *data = (uint8_t *)"";
uint8_t *start;
int ret = 0;
if (avpkt->size) {
if (avpkt->buf) {
buf = av_buffer_ref(avpkt->buf);
size = avpkt->size;
data = avpkt->data;
} else {
buf = av_buffer_alloc(avpkt->size);
if (buf) {
memcpy(buf->data, avpkt->data, avpkt->size);
size = buf->size;
data = buf->data;
}
}
if (!buf) {
ret = AVERROR(ENOMEM);
goto done;
}
if (!is_extradata)
ctx->packets_sent++;
} else {
if (ctx->eos_sent)
goto done;
if (!ctx->packets_sent) {
// Short-cut the flush logic to avoid upsetting MMAL.
ctx->eos_sent = 1;
ctx->eos_received = 1;
goto done;
}
}
start = data;
do {
FFBufferEntry *buffer = av_mallocz(sizeof(*buffer));
if (!buffer) {
ret = AVERROR(ENOMEM);
goto done;
}
buffer->data = data;
buffer->length = FFMIN(size, ctx->decoder->input[0]->buffer_size);
if (is_extradata)
buffer->flags |= MMAL_BUFFER_HEADER_FLAG_CONFIG;
if (data == start)
buffer->flags |= MMAL_BUFFER_HEADER_FLAG_FRAME_START;
data += buffer->length;
size -= buffer->length;
buffer->pts = avpkt->pts == AV_NOPTS_VALUE ? MMAL_TIME_UNKNOWN : avpkt->pts;
buffer->dts = avpkt->dts == AV_NOPTS_VALUE ? MMAL_TIME_UNKNOWN : avpkt->dts;
if (!size) {
buffer->flags |= MMAL_BUFFER_HEADER_FLAG_FRAME_END;
atomic_fetch_add(&ctx->packets_buffered, 1);
}
if (!buffer->length) {
buffer->flags |= MMAL_BUFFER_HEADER_FLAG_EOS;
ctx->eos_sent = 1;
}
if (buf) {
buffer->ref = av_buffer_ref(buf);
if (!buffer->ref) {
av_free(buffer);
ret = AVERROR(ENOMEM);
goto done;
}
}
// Insert at end of the list
if (!ctx->waiting_buffers)
ctx->waiting_buffers = buffer;
if (ctx->waiting_buffers_tail)
ctx->waiting_buffers_tail->next = buffer;
ctx->waiting_buffers_tail = buffer;
} while (size);
done:
av_buffer_unref(&buf);
return ret;
}
// Move prepared/split packets from waiting_buffers to the MMAL decoder.
static int ffmmal_fill_input_port(AVCodecContext *avctx)
{
MMALDecodeContext *ctx = avctx->priv_data;
while (ctx->waiting_buffers) {
MMAL_BUFFER_HEADER_T *mbuffer;
FFBufferEntry *buffer;
MMAL_STATUS_T status;
mbuffer = mmal_queue_get(ctx->pool_in->queue);
if (!mbuffer)
return 0;
buffer = ctx->waiting_buffers;
mmal_buffer_header_reset(mbuffer);
mbuffer->cmd = 0;
mbuffer->pts = buffer->pts;
mbuffer->dts = buffer->dts;
mbuffer->flags = buffer->flags;
mbuffer->data = buffer->data;
mbuffer->length = buffer->length;
mbuffer->user_data = buffer;
mbuffer->alloc_size = ctx->decoder->input[0]->buffer_size;
// Remove from start of the list
ctx->waiting_buffers = buffer->next;
if (ctx->waiting_buffers_tail == buffer)
ctx->waiting_buffers_tail = NULL;
if ((status = mmal_port_send_buffer(ctx->decoder->input[0], mbuffer))) {
mmal_buffer_header_release(mbuffer);
av_buffer_unref(&buffer->ref);
if (buffer->flags & MMAL_BUFFER_HEADER_FLAG_FRAME_END)
atomic_fetch_add(&ctx->packets_buffered, -1);
av_free(buffer);
}
if (status) {
av_log(avctx, AV_LOG_ERROR, "MMAL error %d when sending input\n", (int)status);
return AVERROR_UNKNOWN;
}
}
return 0;
}
static int ffmal_copy_frame(AVCodecContext *avctx, AVFrame *frame,
MMAL_BUFFER_HEADER_T *buffer)
{
MMALDecodeContext *ctx = avctx->priv_data;
int ret = 0;
frame->interlaced_frame = ctx->interlaced_frame;
frame->top_field_first = ctx->top_field_first;
if (avctx->pix_fmt == AV_PIX_FMT_MMAL) {
if (!ctx->pool_out)
return AVERROR_UNKNOWN; // format change code failed with OOM previously
if ((ret = ff_decode_frame_props(avctx, frame)) < 0)
goto done;
if ((ret = ffmmal_set_ref(frame, ctx->pool_out, buffer)) < 0)
goto done;
} else {
int w = FFALIGN(avctx->width, 32);
int h = FFALIGN(avctx->height, 16);
uint8_t *src[4];
int linesize[4];
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
goto done;
av_image_fill_arrays(src, linesize,
buffer->data + buffer->type->video.offset[0],
avctx->pix_fmt, w, h, 1);
av_image_copy(frame->data, frame->linesize, src, linesize,
avctx->pix_fmt, avctx->width, avctx->height);
}
frame->pts = buffer->pts == MMAL_TIME_UNKNOWN ? AV_NOPTS_VALUE : buffer->pts;
#if FF_API_PKT_PTS
FF_DISABLE_DEPRECATION_WARNINGS
frame->pkt_pts = frame->pts;
FF_ENABLE_DEPRECATION_WARNINGS
#endif
frame->pkt_dts = AV_NOPTS_VALUE;
done:
return ret;
}
// Fetch a decoded buffer and place it into the frame parameter.
static int ffmmal_read_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame)
{
MMALDecodeContext *ctx = avctx->priv_data;
MMAL_BUFFER_HEADER_T *buffer = NULL;
MMAL_STATUS_T status = 0;
int ret = 0;
if (ctx->eos_received)
goto done;
while (1) {
// To ensure decoding in lockstep with a constant delay between fed packets
// and output frames, we always wait until an output buffer is available.
// Except during start we don't know after how many input packets the decoder
// is going to return the first buffer, and we can't distinguish decoder
// being busy from decoder waiting for input. So just poll at the start and
// keep feeding new data to the buffer.
// We are pretty sure the decoder will produce output if we sent more input
// frames than what a H.264 decoder could logically delay. This avoids too
// excessive buffering.
// We also wait if we sent eos, but didn't receive it yet (think of decoding
// stream with a very low number of frames).
if (atomic_load(&ctx->packets_buffered) > MAX_DELAYED_FRAMES ||
(ctx->packets_sent && ctx->eos_sent)) {
// MMAL will ignore broken input packets, which means the frame we
// expect here may never arrive. Dealing with this correctly is
// complicated, so here's a hack to avoid that it freezes forever
// in this unlikely situation.
buffer = mmal_queue_timedwait(ctx->queue_decoded_frames, 100);
if (!buffer) {
av_log(avctx, AV_LOG_ERROR, "Did not get output frame from MMAL.\n");
ret = AVERROR_UNKNOWN;
goto done;
}
} else {
buffer = mmal_queue_get(ctx->queue_decoded_frames);
if (!buffer)
goto done;
}
ctx->eos_received |= !!(buffer->flags & MMAL_BUFFER_HEADER_FLAG_EOS);
if (ctx->eos_received)
goto done;
if (buffer->cmd == MMAL_EVENT_FORMAT_CHANGED) {
MMAL_COMPONENT_T *decoder = ctx->decoder;
MMAL_EVENT_FORMAT_CHANGED_T *ev = mmal_event_format_changed_get(buffer);
MMAL_BUFFER_HEADER_T *stale_buffer;
av_log(avctx, AV_LOG_INFO, "Changing output format.\n");
if ((status = mmal_port_disable(decoder->output[0])))
goto done;
while ((stale_buffer = mmal_queue_get(ctx->queue_decoded_frames)))
mmal_buffer_header_release(stale_buffer);
mmal_format_copy(decoder->output[0]->format, ev->format);
if ((ret = ffmal_update_format(avctx)) < 0)
goto done;
if ((status = mmal_port_enable(decoder->output[0], output_callback)))
goto done;
if ((ret = ffmmal_fill_output_port(avctx)) < 0)
goto done;
if ((ret = ffmmal_fill_input_port(avctx)) < 0)
goto done;
mmal_buffer_header_release(buffer);
continue;
} else if (buffer->cmd) {
char s[20];
av_get_codec_tag_string(s, sizeof(s), buffer->cmd);
av_log(avctx, AV_LOG_WARNING, "Unknown MMAL event %s on output port\n", s);
goto done;
} else if (buffer->length == 0) {
// Unused output buffer that got drained after format change.
mmal_buffer_header_release(buffer);
continue;
}
ctx->frames_output++;
if ((ret = ffmal_copy_frame(avctx, frame, buffer)) < 0)
goto done;
*got_frame = 1;
break;
}
done:
if (buffer)
mmal_buffer_header_release(buffer);
if (status && ret >= 0)
ret = AVERROR_UNKNOWN;
return ret;
}
static int ffmmal_decode(AVCodecContext *avctx, void *data, int *got_frame,
AVPacket *avpkt)
{
MMALDecodeContext *ctx = avctx->priv_data;
AVFrame *frame = data;
int ret = 0;
if (avctx->extradata_size && !ctx->extradata_sent) {
AVPacket pkt = {0};
av_init_packet(&pkt);
pkt.data = avctx->extradata;
pkt.size = avctx->extradata_size;
ctx->extradata_sent = 1;
if ((ret = ffmmal_add_packet(avctx, &pkt, 1)) < 0)
return ret;
}
if ((ret = ffmmal_add_packet(avctx, avpkt, 0)) < 0)
return ret;
if ((ret = ffmmal_fill_input_port(avctx)) < 0)
return ret;
if ((ret = ffmmal_fill_output_port(avctx)) < 0)
return ret;
if ((ret = ffmmal_read_frame(avctx, frame, got_frame)) < 0)
return ret;
// ffmmal_read_frame() can block for a while. Since the decoder is
// asynchronous, it's a good idea to fill the ports again.
if ((ret = ffmmal_fill_output_port(avctx)) < 0)
return ret;
if ((ret = ffmmal_fill_input_port(avctx)) < 0)
return ret;
return ret;
}
AVHWAccel ff_h264_mmal_hwaccel = {
.name = "h264_mmal",
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_H264,
.pix_fmt = AV_PIX_FMT_MMAL,
};
AVHWAccel ff_mpeg2_mmal_hwaccel = {
.name = "mpeg2_mmal",
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_MPEG2VIDEO,
.pix_fmt = AV_PIX_FMT_MMAL,
};
AVHWAccel ff_mpeg4_mmal_hwaccel = {
.name = "mpeg4_mmal",
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_MPEG4,
.pix_fmt = AV_PIX_FMT_MMAL,
};
AVHWAccel ff_vc1_mmal_hwaccel = {
.name = "vc1_mmal",
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_VC1,
.pix_fmt = AV_PIX_FMT_MMAL,
};
static const AVOption options[]={
{"extra_buffers", "extra buffers", offsetof(MMALDecodeContext, extra_buffers), AV_OPT_TYPE_INT, {.i64 = 10}, 0, 256, 0},
{"extra_decoder_buffers", "extra MMAL internal buffered frames", offsetof(MMALDecodeContext, extra_decoder_buffers), AV_OPT_TYPE_INT, {.i64 = 10}, 0, 256, 0},
{NULL}
};
#define FFMMAL_DEC_CLASS(NAME) \
static const AVClass ffmmal_##NAME##_dec_class = { \
.class_name = "mmal_" #NAME "_dec", \
.option = options, \
.version = LIBAVUTIL_VERSION_INT, \
};
#define FFMMAL_DEC(NAME, ID) \
FFMMAL_DEC_CLASS(NAME) \
AVCodec ff_##NAME##_mmal_decoder = { \
.name = #NAME "_mmal", \
.long_name = NULL_IF_CONFIG_SMALL(#NAME " (mmal)"), \
.type = AVMEDIA_TYPE_VIDEO, \
.id = ID, \
.priv_data_size = sizeof(MMALDecodeContext), \
.init = ffmmal_init_decoder, \
.close = ffmmal_close_decoder, \
.decode = ffmmal_decode, \
.flush = ffmmal_flush, \
.priv_class = &ffmmal_##NAME##_dec_class, \
.capabilities = AV_CODEC_CAP_DELAY, \
.caps_internal = FF_CODEC_CAP_SETS_PKT_DTS, \
.pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_MMAL, \
AV_PIX_FMT_YUV420P, \
AV_PIX_FMT_NONE}, \
};
FFMMAL_DEC(h264, AV_CODEC_ID_H264)
FFMMAL_DEC(mpeg2, AV_CODEC_ID_MPEG2VIDEO)
FFMMAL_DEC(mpeg4, AV_CODEC_ID_MPEG4)
FFMMAL_DEC(vc1, AV_CODEC_ID_VC1)